Discussion:
Is spacetime curvature really enough to replace gravity?
(too old to reply)
Tim Golden BandTech.com
2011-01-26 14:44:11 UTC
Permalink
No. It is not, and a simple argument is enough to see it. Why has this
interpretation become accepted? Surely this is a statement on the
human mind.

The argument is constructed simply.

1. We understand that bodies which are not under the influence of
other bodies will carry on in a straight path regardless of their
relative velocity. This is one of Newton's laws which is akin to the
term 'inertia'. I do not challenge this precept and instead see that
the claims of spatial curvature are not enough to reuse this law in
the gravitational setting.

2. General Relativity claims that the mass of a body causes spatial
curvature, thus altering what to an inertial body would see as its
straight line path. This supposedly explains the orbits of planetary
bodies around the sun as well as our own attraction to the earth
beneath our feet. However, the spatial curvature is regarded as a
constant regardless of a body's velocity. This would mean that a high
velocity body would travel the same trajectory as a low velocity body
under the curved space interpretation. We know that this is not true,
and that a body with greater velocity will travel a different path.
The higher the body's velocity, the straighter will be its path.
Therefor the space curvature interpretation is suspect.

Here is a quote from the current wikipedia page:
"General relativity is a metric theory of gravitation. At its core
are Einstein's equations, which describe the relation between the
geometry of a four-dimensional, pseudo-Riemannian manifold
representing spacetime, and the energy-momentum contained in that
spacetime.[31] Phenomena that in classical mechanics are ascribed to
the action of the force of gravity (such as free-fall, orbital motion,
and spacecraft trajectories), correspond to inertial motion within a
curved geometry of spacetime in general relativity; there is no
gravitational force deflecting objects from their natural, straight
paths. Instead, gravity corresponds to changes in the properties of
space and time, which in turn changes the straightest-possible paths
that objects will naturally follow.[32] The curvature is, in turn,
caused by the energy-momentum of matter. Paraphrasing the relativist
John Archibald Wheeler, spacetime tells matter how to move; matter
tells spacetime how to curve.[33]"
- http://en.wikipedia.org/wiki/General_relativity#Definition_and_basic_properties

I believe that the criticism I am harboring goes beyond the layman's
interpretations, for here is a fairly technical interpretation which
still has blatant disregard for velocity. This means that if we were
to accelerate the earth in its course that it would hold course in its
current orbit. This is a false statement and corrections should be
made. Whether the corrections are in my own interpretation of the
above information, well, I am open to that. Still, I am likewise open
to corrections being made in the numerous texts that exist on the
other side of the supposed conflict. If I am correct then this is one
more stage of support for the stupidity of humanity. Still, even if we
are stupid, we have to work with what we've got. This means keeping
things simple, and I believe that the simplicity of my own argument
can be whittled down to just a few lines:

If space is curved, then the force free paths ('straight')
through that curved space
have no dependence upon an object's velocity along those paths.

This statement essentially challenges the construction of curved
space, but I do not need to go this far in order to launch the
criticism. Please note that the defense of relativity theory by
experiment does not void this criticism. The curve fitters paradigm is
not pure theory. Here if I have to extend my criticism it is that the
theory requires revision in order to come clean, and that somehow
working with the tools that were available Einstein (and others)
managed to do quite well, but perhaps the models running in his head
were even cleaner than those that he was able to pen. Perhaps we are
still missing some fundamental tools.

- Tim
William Hughes
2011-01-26 14:50:53 UTC
Permalink
spatial curvature and spacetime curvature are not the same thing.
Androcles
2011-01-26 19:32:20 UTC
Permalink
"William Hughes" <***@gmail.com> wrote in message news:44deb1aa-2e08-4822-b474-***@j19g2000prh.googlegroups.com...
| spatial curvature and spacetime curvature are not the same thing.
|
Dogs and cats are not the same thing.
Apples and pears are not the same thing.
Any stupid fuck can say what something isn't.
Ignorant bigot and William Hughes IS the same thing.
mpc755
2011-01-26 15:57:46 UTC
Permalink
Post by Tim Golden BandTech.com
No. It is not, and a simple argument is enough to see it. Why has this
interpretation become accepted? Surely this is a statement on the
human mind.
The argument is constructed simply.
   1. We understand that bodies which are not under the influence of
other bodies will carry on in a straight path regardless of their
relative velocity. This is one of Newton's laws which is akin to the
term 'inertia'. I do not challenge this precept and instead see that
the claims of spatial curvature are not enough to reuse this law in
the gravitational setting.
   2. General Relativity claims that the mass of a body causes spatial
curvature, thus altering what to an inertial body would see as its
straight line path. This supposedly explains the orbits of planetary
bodies around the sun as well as our own attraction to the earth
beneath our feet. However, the spatial curvature is regarded as a
constant regardless of a body's velocity. This would mean that a high
velocity body would travel the same trajectory as a low velocity body
under the curved space interpretation. We know that this is not true,
and that a body with greater velocity will travel a different path.
The higher the body's velocity, the straighter will be its path.
Therefor the space curvature interpretation is suspect.
   "General relativity is a metric theory of gravitation. At its core
are Einstein's equations, which describe the relation between the
geometry of a four-dimensional, pseudo-Riemannian manifold
representing spacetime, and the energy-momentum contained in that
spacetime.[31] Phenomena that in classical mechanics are ascribed to
the action of the force of gravity (such as free-fall, orbital motion,
and spacecraft trajectories), correspond to inertial motion within a
curved geometry of spacetime in general relativity; there is no
gravitational force deflecting objects from their natural, straight
paths. Instead, gravity corresponds to changes in the properties of
space and time, which in turn changes the straightest-possible paths
that objects will naturally follow.[32] The curvature is, in turn,
caused by the energy-momentum of matter. Paraphrasing the relativist
John Archibald Wheeler, spacetime tells matter how to move; matter
tells spacetime how to curve.[33]"
 -http://en.wikipedia.org/wiki/General_relativity#Definition_and_basic_...
I believe that the criticism I am harboring goes beyond the layman's
interpretations, for here is a fairly technical interpretation which
still has blatant disregard for velocity. This means that if we were
to accelerate the earth in its course that it would hold course in its
current orbit. This is a false statement and corrections should be
made. Whether the corrections are in my own interpretation of the
above information, well, I am open to that. Still, I am likewise open
to corrections being made in the numerous texts that exist on the
other side of the supposed conflict. If I am correct then this is one
more stage of support for the stupidity of humanity. Still, even if we
are stupid, we have to work with what we've got. This means keeping
things simple, and I believe that the simplicity of my own argument
      If space is curved, then the force free paths ('straight')
through that curved space
      have no dependence upon an object's velocity along those paths.
This statement essentially challenges the construction of curved
space, but I do not need to go this far in order to launch the
criticism. Please note that the defense of relativity theory by
experiment does not void this criticism. The curve fitters paradigm is
not pure theory. Here if I have to extend my criticism it is that the
theory requires revision in order to come clean, and that somehow
working with the tools that were available Einstein (and others)
managed to do quite well, but perhaps the models running in his head
were even cleaner than those that he was able to pen. Perhaps we are
still missing some fundamental tools.
 - Tim
Curved spacetime is displaced aether.

Einstein's 'First Paper'
http://www.worldscibooks.com/etextbook/4454/4454_chap1.pdf

"I believe that for the understanding of electromagnetic phenomena it
is important also to undertake a comprehensive experimental
investigation of the potential states of the aether in magnetic fields
of all kinds — or, in other words, to measure the elastic deformations
and the acting deforming forces."

Einstein understood aether displacement as 'elastic deformations' and
understood the associated force as the 'acting deforming forces'.

The 'elastic deformations' is displaced aether.

'Ether and the Theory of Relativity - Albert Einstein'
http://www.tu-harburg.de/rzt/rzt/it/Ether.html

What Einstein is referring to throughout the article is the aether's
state of displacement.

"the state of the [ether] is at every place determined by connections
with the matter and the state of the ether in neighbouring places, ...
disregarding the causes which condition its state."

The state of the aether as determined by its connections with the
matter and the state of the aether in neighboring places is the
aether's state of displacement. The cause which conditions its state
is its displacement by matter.

Force exerted towards matter by aether displaced by matter is gravity.
dlzc
2011-01-26 16:19:44 UTC
Permalink
Post by Tim Golden BandTech.com
No. It is not, and a simple argument is enough to
see it. Why has this interpretation become
accepted? Surely this is a statement on the
human mind.
Yes, your statement is a statement about your mind, and your inability
to form a logical argument.
Post by Tim Golden BandTech.com
The argument is constructed simply.
   1. We understand that bodies which are not
under the influence of other bodies will carry on
in a straight path regardless of their relative
velocity.
Neglecting "gravitation" and "charge".
Post by Tim Golden BandTech.com
This is one of Newton's laws which is akin to the
term 'inertia'. I do not challenge this precept and
instead see that the claims of spatial curvature are
not enough to reuse this law in the gravitational
setting.
As has already been said, "spatial curvature" isn't what General
Relativity is about. The "rubber sheet" analogy is for babies.
Post by Tim Golden BandTech.com
   2. General Relativity claims that the mass of a
body causes spatial curvature,
No, it does not.
Post by Tim Golden BandTech.com
thus altering what to an inertial body would see as
its straight line path. This supposedly explains the
orbits of planetary bodies around the sun as well as
our own attraction to the earth beneath our feet.
No, it is not "attraction" in GR, it is that the soil is pushing you
off your force-free orbit.
Post by Tim Golden BandTech.com
However, the spatial curvature is regarded as a
constant regardless of a body's velocity.
Not "regardless", just a very weak function. The "energy of motion"
does contribute to local curvature, its just not a lot of "equivalent
mass" until you are moving very fast... and the effects could likely
on be measured over light years.
Post by Tim Golden BandTech.com
This would mean that a high velocity body would
travel the same trajectory as a low velocity body
under the curved space interpretation.
No, it does not. If you knew Newton as you claim, you'd be aware of
the concept of "impulse". A constant force over a variable period of
time, results in different trajectories.
Post by Tim Golden BandTech.com
We know that this is not true, and that a body with
greater velocity will travel a different path. The higher
the body's velocity, the straighter will be its path.
Therefor the space curvature interpretation is suspect.
No, your understanding of even Newtonian physics is suspect. And
clearly you haven't a clue about Relativity, which you seek to
critique based on your misconceptions.
Post by Tim Golden BandTech.com
   "General relativity is a metric theory of gravitation.
At its core are Einstein's equations, which describe
the relation between the geometry of a four-dimensional,
pseudo-Riemannian manifold representing spacetime,
and the energy-momentum contained in that
spacetime.[31] Phenomena that in classical mechanics
are ascribed to the action of the force of gravity (such as
free-fall, orbital motion, and spacecraft trajectories),
correspond to inertial motion within a curved geometry
of spacetime in general relativity; there is no
gravitational force deflecting objects from their natural,
straight paths. Instead, gravity corresponds to changes
in the properties of space and time,
Note: they are a *set*.
Post by Tim Golden BandTech.com
which in turn changes the straightest-possible paths
that objects will naturally follow.[32] The curvature is,
in turn, caused by the energy-momentum of matter.
Paraphrasing the relativist John Archibald Wheeler,
spacetime tells matter how to move; matter tells
spacetime how to curve.[33]"
 -http://en.wikipedia.org/wiki/General_relativity#Definition_and_basic_...
I believe that the criticism I am harboring goes
beyond the layman's interpretations,
Clearly untrue, since you are at least as ignorant of enven Newtonian
physics and logic as the average grade school child.

<snip the rest of your painfull to see drivel>

...
Post by Tim Golden BandTech.com
Perhaps we are still missing some fundamental tools.
The truth comes out, if *you* are conatined in "we". One of those
tools is use of your brain for something other than pressing "Send".

David A. Smith
mpc755
2011-01-26 16:22:12 UTC
Permalink
Post by dlzc
Post by Tim Golden BandTech.com
No. It is not, and a simple argument is enough to
see it. Why has this interpretation become
accepted? Surely this is a statement on the
human mind.
Yes, your statement is a statement about your mind, and your inability
to form a logical argument.
Post by Tim Golden BandTech.com
The argument is constructed simply.
   1. We understand that bodies which are not
under the influence of other bodies will carry on
in a straight path regardless of their relative
velocity.
Neglecting "gravitation" and "charge".
Post by Tim Golden BandTech.com
This is one of Newton's laws which is akin to the
term 'inertia'. I do not challenge this precept and
instead see that the claims of spatial curvature are
not enough to reuse this law in the gravitational
setting.
As has already been said, "spatial curvature" isn't what General
Relativity is about.  The "rubber sheet" analogy is for babies.
Post by Tim Golden BandTech.com
   2. General Relativity claims that the mass of a
body causes spatial curvature,
No, it does not.
Post by Tim Golden BandTech.com
thus altering what to an inertial body would see as
its straight line path. This supposedly explains the
orbits of planetary bodies around the sun as well as
our own attraction to the earth beneath our feet.
No, it is not "attraction" in GR, it is that the soil is pushing you
off your force-free orbit.
Post by Tim Golden BandTech.com
However, the spatial curvature is regarded as a
constant regardless of a body's velocity.
Not "regardless", just a very weak function.  The "energy of motion"
does contribute to local curvature, its just not a lot of "equivalent
mass" until you are moving very fast... and the effects could likely
on be measured over light years.
Post by Tim Golden BandTech.com
This would mean that a high velocity body would
travel the same trajectory as a low velocity body
under the curved space interpretation.
No, it does not.  If you knew Newton as you claim, you'd be aware of
the concept of "impulse".  A constant force over a variable period of
time, results in different trajectories.
Post by Tim Golden BandTech.com
We know that this is not true, and that a body with
greater velocity will travel a different path.  The higher
the body's velocity, the straighter will be its path.
Therefor the space curvature interpretation is suspect.
No, your understanding of even Newtonian physics is suspect.  And
clearly you haven't a clue about Relativity, which you seek to
critique based on your misconceptions.
Post by Tim Golden BandTech.com
   "General relativity is a metric theory of gravitation.
At its core are Einstein's equations, which describe
the relation between the geometry of a four-dimensional,
pseudo-Riemannian manifold representing spacetime,
and the energy-momentum contained in that
spacetime.[31] Phenomena that in classical mechanics
are ascribed to the action of the force of gravity (such as
free-fall, orbital motion, and spacecraft trajectories),
correspond to inertial motion within a curved geometry
of spacetime in general relativity; there is no
gravitational force deflecting objects from their natural,
straight paths. Instead, gravity corresponds to changes
in the properties of space and time,
Note: they are a *set*.
Post by Tim Golden BandTech.com
which in turn changes the straightest-possible paths
that objects will naturally follow.[32] The curvature is,
in turn, caused by the energy-momentum of matter.
Paraphrasing the relativist John Archibald Wheeler,
spacetime tells matter how to move; matter tells
spacetime how to curve.[33]"
 -http://en.wikipedia.org/wiki/General_relativity#Definition_and_basic_...
I believe that the criticism I am harboring goes
beyond the layman's interpretations,
Clearly untrue, since you are at least as ignorant of enven Newtonian
physics and logic as the average grade school child.
<snip the rest of your painfull to see drivel>
...
Post by Tim Golden BandTech.com
Perhaps we are still missing some fundamental tools.
The truth comes out, if *you* are conatined in "we".  One of those
tools is use of your brain for something other than pressing "Send".
David A. Smith
Explain what occurs physically in nature to cause gravity.

What's that? You can't?

Aether has mass.
Aether is displaced by matter.
Displaced aether is not at rest.
Displaced aether exerts force towards matter.
Force exerted towards matter by aether displaced by matter is gravity.
PD
2011-01-26 18:20:48 UTC
Permalink
Post by mpc755
Post by dlzc
Post by Tim Golden BandTech.com
No. It is not, and a simple argument is enough to
see it. Why has this interpretation become
accepted? Surely this is a statement on the
human mind.
Yes, your statement is a statement about your mind, and your inability
to form a logical argument.
Post by Tim Golden BandTech.com
The argument is constructed simply.
   1. We understand that bodies which are not
under the influence of other bodies will carry on
in a straight path regardless of their relative
velocity.
Neglecting "gravitation" and "charge".
Post by Tim Golden BandTech.com
This is one of Newton's laws which is akin to the
term 'inertia'. I do not challenge this precept and
instead see that the claims of spatial curvature are
not enough to reuse this law in the gravitational
setting.
As has already been said, "spatial curvature" isn't what General
Relativity is about.  The "rubber sheet" analogy is for babies.
Post by Tim Golden BandTech.com
   2. General Relativity claims that the mass of a
body causes spatial curvature,
No, it does not.
Post by Tim Golden BandTech.com
thus altering what to an inertial body would see as
its straight line path. This supposedly explains the
orbits of planetary bodies around the sun as well as
our own attraction to the earth beneath our feet.
No, it is not "attraction" in GR, it is that the soil is pushing you
off your force-free orbit.
Post by Tim Golden BandTech.com
However, the spatial curvature is regarded as a
constant regardless of a body's velocity.
Not "regardless", just a very weak function.  The "energy of motion"
does contribute to local curvature, its just not a lot of "equivalent
mass" until you are moving very fast... and the effects could likely
on be measured over light years.
Post by Tim Golden BandTech.com
This would mean that a high velocity body would
travel the same trajectory as a low velocity body
under the curved space interpretation.
No, it does not.  If you knew Newton as you claim, you'd be aware of
the concept of "impulse".  A constant force over a variable period of
time, results in different trajectories.
Post by Tim Golden BandTech.com
We know that this is not true, and that a body with
greater velocity will travel a different path.  The higher
the body's velocity, the straighter will be its path.
Therefor the space curvature interpretation is suspect.
No, your understanding of even Newtonian physics is suspect.  And
clearly you haven't a clue about Relativity, which you seek to
critique based on your misconceptions.
Post by Tim Golden BandTech.com
   "General relativity is a metric theory of gravitation.
At its core are Einstein's equations, which describe
the relation between the geometry of a four-dimensional,
pseudo-Riemannian manifold representing spacetime,
and the energy-momentum contained in that
spacetime.[31] Phenomena that in classical mechanics
are ascribed to the action of the force of gravity (such as
free-fall, orbital motion, and spacecraft trajectories),
correspond to inertial motion within a curved geometry
of spacetime in general relativity; there is no
gravitational force deflecting objects from their natural,
straight paths. Instead, gravity corresponds to changes
in the properties of space and time,
Note: they are a *set*.
Post by Tim Golden BandTech.com
which in turn changes the straightest-possible paths
that objects will naturally follow.[32] The curvature is,
in turn, caused by the energy-momentum of matter.
Paraphrasing the relativist John Archibald Wheeler,
spacetime tells matter how to move; matter tells
spacetime how to curve.[33]"
 -http://en.wikipedia.org/wiki/General_relativity#Definition_and_basic_...
I believe that the criticism I am harboring goes
beyond the layman's interpretations,
Clearly untrue, since you are at least as ignorant of enven Newtonian
physics and logic as the average grade school child.
<snip the rest of your painfull to see drivel>
...
Post by Tim Golden BandTech.com
Perhaps we are still missing some fundamental tools.
The truth comes out, if *you* are conatined in "we".  One of those
tools is use of your brain for something other than pressing "Send".
David A. Smith
Explain what occurs physically in nature to cause gravity.
Mike Cavedon sez, "I'll say what I want repeatedly and call it correct
as long as you continue to refuse my petty demands to explain
otherwise in a manner than I consider acceptable."
Howzatworkinferya?
Post by mpc755
What's that? You can't?
Aether has mass.
Aether is displaced by matter.
Displaced aether is not at rest.
Displaced aether exerts force towards matter.
Force exerted towards matter by aether displaced by matter is gravity.
mpc755
2011-01-26 18:33:42 UTC
Permalink
Post by PD
Post by mpc755
Post by dlzc
Post by Tim Golden BandTech.com
No. It is not, and a simple argument is enough to
see it. Why has this interpretation become
accepted? Surely this is a statement on the
human mind.
Yes, your statement is a statement about your mind, and your inability
to form a logical argument.
Post by Tim Golden BandTech.com
The argument is constructed simply.
   1. We understand that bodies which are not
under the influence of other bodies will carry on
in a straight path regardless of their relative
velocity.
Neglecting "gravitation" and "charge".
Post by Tim Golden BandTech.com
This is one of Newton's laws which is akin to the
term 'inertia'. I do not challenge this precept and
instead see that the claims of spatial curvature are
not enough to reuse this law in the gravitational
setting.
As has already been said, "spatial curvature" isn't what General
Relativity is about.  The "rubber sheet" analogy is for babies.
Post by Tim Golden BandTech.com
   2. General Relativity claims that the mass of a
body causes spatial curvature,
No, it does not.
Post by Tim Golden BandTech.com
thus altering what to an inertial body would see as
its straight line path. This supposedly explains the
orbits of planetary bodies around the sun as well as
our own attraction to the earth beneath our feet.
No, it is not "attraction" in GR, it is that the soil is pushing you
off your force-free orbit.
Post by Tim Golden BandTech.com
However, the spatial curvature is regarded as a
constant regardless of a body's velocity.
Not "regardless", just a very weak function.  The "energy of motion"
does contribute to local curvature, its just not a lot of "equivalent
mass" until you are moving very fast... and the effects could likely
on be measured over light years.
Post by Tim Golden BandTech.com
This would mean that a high velocity body would
travel the same trajectory as a low velocity body
under the curved space interpretation.
No, it does not.  If you knew Newton as you claim, you'd be aware of
the concept of "impulse".  A constant force over a variable period of
time, results in different trajectories.
Post by Tim Golden BandTech.com
We know that this is not true, and that a body with
greater velocity will travel a different path.  The higher
the body's velocity, the straighter will be its path.
Therefor the space curvature interpretation is suspect.
No, your understanding of even Newtonian physics is suspect.  And
clearly you haven't a clue about Relativity, which you seek to
critique based on your misconceptions.
Post by Tim Golden BandTech.com
   "General relativity is a metric theory of gravitation.
At its core are Einstein's equations, which describe
the relation between the geometry of a four-dimensional,
pseudo-Riemannian manifold representing spacetime,
and the energy-momentum contained in that
spacetime.[31] Phenomena that in classical mechanics
are ascribed to the action of the force of gravity (such as
free-fall, orbital motion, and spacecraft trajectories),
correspond to inertial motion within a curved geometry
of spacetime in general relativity; there is no
gravitational force deflecting objects from their natural,
straight paths. Instead, gravity corresponds to changes
in the properties of space and time,
Note: they are a *set*.
Post by Tim Golden BandTech.com
which in turn changes the straightest-possible paths
that objects will naturally follow.[32] The curvature is,
in turn, caused by the energy-momentum of matter.
Paraphrasing the relativist John Archibald Wheeler,
spacetime tells matter how to move; matter tells
spacetime how to curve.[33]"
 -http://en.wikipedia.org/wiki/General_relativity#Definition_and_basic_...
I believe that the criticism I am harboring goes
beyond the layman's interpretations,
Clearly untrue, since you are at least as ignorant of enven Newtonian
physics and logic as the average grade school child.
<snip the rest of your painfull to see drivel>
...
Post by Tim Golden BandTech.com
Perhaps we are still missing some fundamental tools.
The truth comes out, if *you* are conatined in "we".  One of those
tools is use of your brain for something other than pressing "Send".
David A. Smith
Explain what occurs physically in nature to cause gravity.
Mike Cavedon sez, "I'll say what I want repeatedly and call it correct
as long as you continue to refuse my petty demands to explain
otherwise in a manner than I consider acceptable."
Howzatworkinferya?
The other poster made statements such as:

"Yes, your statement is a statement about your mind, and your
inability to form a logical argument."

"No, it is not "attraction" in GR, it is that the soil is pushing you
off your force-free orbit."

"Clearly untrue, since you are at least as ignorant of enven Newtonian
physics and logic as the average grade school child."

I'm simply asking the poster, who seems to act as if they have it all
figured out to explain what occurs physically in nature to cause
gravity.

Certainly someone who makes such statements as the poster does and
insists gravity is "the soil pushing you off your force-free orbit"
should be able to explain what is occurring physically in nature to
cause you to be pushed off your force-free orbit.

Unless of course as statement such as the above is simply more
ridiculous absurd nonsense associated with those who think they
understand the physics of nature.

Aether has mass.
Aether is displaced by matter.
Displaced aether is not at rest.
Displaced aether exerts force towards matter.
Force exerted towards matter by aether displaced by matter is gravity.
PD
2011-01-26 19:32:28 UTC
Permalink
Post by mpc755
Post by PD
Post by mpc755
Post by dlzc
Post by Tim Golden BandTech.com
No. It is not, and a simple argument is enough to
see it. Why has this interpretation become
accepted? Surely this is a statement on the
human mind.
Yes, your statement is a statement about your mind, and your inability
to form a logical argument.
Post by Tim Golden BandTech.com
The argument is constructed simply.
   1. We understand that bodies which are not
under the influence of other bodies will carry on
in a straight path regardless of their relative
velocity.
Neglecting "gravitation" and "charge".
Post by Tim Golden BandTech.com
This is one of Newton's laws which is akin to the
term 'inertia'. I do not challenge this precept and
instead see that the claims of spatial curvature are
not enough to reuse this law in the gravitational
setting.
As has already been said, "spatial curvature" isn't what General
Relativity is about.  The "rubber sheet" analogy is for babies.
Post by Tim Golden BandTech.com
   2. General Relativity claims that the mass of a
body causes spatial curvature,
No, it does not.
Post by Tim Golden BandTech.com
thus altering what to an inertial body would see as
its straight line path. This supposedly explains the
orbits of planetary bodies around the sun as well as
our own attraction to the earth beneath our feet.
No, it is not "attraction" in GR, it is that the soil is pushing you
off your force-free orbit.
Post by Tim Golden BandTech.com
However, the spatial curvature is regarded as a
constant regardless of a body's velocity.
Not "regardless", just a very weak function.  The "energy of motion"
does contribute to local curvature, its just not a lot of "equivalent
mass" until you are moving very fast... and the effects could likely
on be measured over light years.
Post by Tim Golden BandTech.com
This would mean that a high velocity body would
travel the same trajectory as a low velocity body
under the curved space interpretation.
No, it does not.  If you knew Newton as you claim, you'd be aware of
the concept of "impulse".  A constant force over a variable period of
time, results in different trajectories.
Post by Tim Golden BandTech.com
We know that this is not true, and that a body with
greater velocity will travel a different path.  The higher
the body's velocity, the straighter will be its path.
Therefor the space curvature interpretation is suspect.
No, your understanding of even Newtonian physics is suspect.  And
clearly you haven't a clue about Relativity, which you seek to
critique based on your misconceptions.
Post by Tim Golden BandTech.com
   "General relativity is a metric theory of gravitation.
At its core are Einstein's equations, which describe
the relation between the geometry of a four-dimensional,
pseudo-Riemannian manifold representing spacetime,
and the energy-momentum contained in that
spacetime.[31] Phenomena that in classical mechanics
are ascribed to the action of the force of gravity (such as
free-fall, orbital motion, and spacecraft trajectories),
correspond to inertial motion within a curved geometry
of spacetime in general relativity; there is no
gravitational force deflecting objects from their natural,
straight paths. Instead, gravity corresponds to changes
in the properties of space and time,
Note: they are a *set*.
Post by Tim Golden BandTech.com
which in turn changes the straightest-possible paths
that objects will naturally follow.[32] The curvature is,
in turn, caused by the energy-momentum of matter.
Paraphrasing the relativist John Archibald Wheeler,
spacetime tells matter how to move; matter tells
spacetime how to curve.[33]"
 -http://en.wikipedia.org/wiki/General_relativity#Definition_and_basic_...
I believe that the criticism I am harboring goes
beyond the layman's interpretations,
Clearly untrue, since you are at least as ignorant of enven Newtonian
physics and logic as the average grade school child.
<snip the rest of your painfull to see drivel>
...
Post by Tim Golden BandTech.com
Perhaps we are still missing some fundamental tools.
The truth comes out, if *you* are conatined in "we".  One of those
tools is use of your brain for something other than pressing "Send".
David A. Smith
Explain what occurs physically in nature to cause gravity.
Mike Cavedon sez, "I'll say what I want repeatedly and call it correct
as long as you continue to refuse my petty demands to explain
otherwise in a manner than I consider acceptable."
Howzatworkinferya?
"Yes, your statement is a statement about your mind, and your
inability to form a logical argument."
"No, it is not "attraction" in GR, it is that the soil is pushing you
off your force-free orbit."
"Clearly untrue, since you are at least as ignorant of enven Newtonian
physics and logic as the average grade school child."
I'm simply asking the poster, who seems to act as if they have it all
figured out to explain what occurs physically in nature to cause
gravity.
You are not owed that explanation of gravity on usenet even by people
who do understand what is physically going on. That's what I pointed
out when I referred to your "petty demands". If you want to understand
what is physically going on, then read something offline rather than
prattle at people on usenet to explain it to you.
Post by mpc755
Certainly someone who makes such statements as the poster does and
insists gravity is "the soil pushing you off your force-free orbit"
should be able to explain what is occurring physically in nature to
cause you to be pushed off your force-free orbit.
Yes, and just because he is able does not mean you are entitled to ask
him to produce it on your demand. This is again what I'm referring to
regarding your "petty demands".
Post by mpc755
Unless of course as statement such as the above is simply more
ridiculous absurd nonsense associated with those who think they
understand the physics of nature.
And this statement has to do with my comment about "in a manner I
consider acceptable".

You will find, Mike, that if you ask someone for money and someone
offers you two quarters or a dollar, and you brush it away saying,
"That's not money," and you do that over and over again, pretty soon
you'll discover that your requests for money handouts will result in
people walking right by you. Not because they don't have the money.
But because you're an ass.
Post by mpc755
Aether has mass.
Aether is displaced by matter.
Displaced aether is not at rest.
Displaced aether exerts force towards matter.
Force exerted towards matter by aether displaced by matter is gravity.
mpc755
2011-01-26 20:20:26 UTC
Permalink
Post by PD
Post by mpc755
Post by PD
Post by mpc755
Post by dlzc
Post by Tim Golden BandTech.com
No. It is not, and a simple argument is enough to
see it. Why has this interpretation become
accepted? Surely this is a statement on the
human mind.
Yes, your statement is a statement about your mind, and your inability
to form a logical argument.
Post by Tim Golden BandTech.com
The argument is constructed simply.
   1. We understand that bodies which are not
under the influence of other bodies will carry on
in a straight path regardless of their relative
velocity.
Neglecting "gravitation" and "charge".
Post by Tim Golden BandTech.com
This is one of Newton's laws which is akin to the
term 'inertia'. I do not challenge this precept and
instead see that the claims of spatial curvature are
not enough to reuse this law in the gravitational
setting.
As has already been said, "spatial curvature" isn't what General
Relativity is about.  The "rubber sheet" analogy is for babies.
Post by Tim Golden BandTech.com
   2. General Relativity claims that the mass of a
body causes spatial curvature,
No, it does not.
Post by Tim Golden BandTech.com
thus altering what to an inertial body would see as
its straight line path. This supposedly explains the
orbits of planetary bodies around the sun as well as
our own attraction to the earth beneath our feet.
No, it is not "attraction" in GR, it is that the soil is pushing you
off your force-free orbit.
Post by Tim Golden BandTech.com
However, the spatial curvature is regarded as a
constant regardless of a body's velocity.
Not "regardless", just a very weak function.  The "energy of motion"
does contribute to local curvature, its just not a lot of "equivalent
mass" until you are moving very fast... and the effects could likely
on be measured over light years.
Post by Tim Golden BandTech.com
This would mean that a high velocity body would
travel the same trajectory as a low velocity body
under the curved space interpretation.
No, it does not.  If you knew Newton as you claim, you'd be aware of
the concept of "impulse".  A constant force over a variable period of
time, results in different trajectories.
Post by Tim Golden BandTech.com
We know that this is not true, and that a body with
greater velocity will travel a different path.  The higher
the body's velocity, the straighter will be its path.
Therefor the space curvature interpretation is suspect.
No, your understanding of even Newtonian physics is suspect.  And
clearly you haven't a clue about Relativity, which you seek to
critique based on your misconceptions.
Post by Tim Golden BandTech.com
   "General relativity is a metric theory of gravitation.
At its core are Einstein's equations, which describe
the relation between the geometry of a four-dimensional,
pseudo-Riemannian manifold representing spacetime,
and the energy-momentum contained in that
spacetime.[31] Phenomena that in classical mechanics
are ascribed to the action of the force of gravity (such as
free-fall, orbital motion, and spacecraft trajectories),
correspond to inertial motion within a curved geometry
of spacetime in general relativity; there is no
gravitational force deflecting objects from their natural,
straight paths. Instead, gravity corresponds to changes
in the properties of space and time,
Note: they are a *set*.
Post by Tim Golden BandTech.com
which in turn changes the straightest-possible paths
that objects will naturally follow.[32] The curvature is,
in turn, caused by the energy-momentum of matter.
Paraphrasing the relativist John Archibald Wheeler,
spacetime tells matter how to move; matter tells
spacetime how to curve.[33]"
 -http://en.wikipedia.org/wiki/General_relativity#Definition_and_basic_...
I believe that the criticism I am harboring goes
beyond the layman's interpretations,
Clearly untrue, since you are at least as ignorant of enven Newtonian
physics and logic as the average grade school child.
<snip the rest of your painfull to see drivel>
...
Post by Tim Golden BandTech.com
Perhaps we are still missing some fundamental tools.
The truth comes out, if *you* are conatined in "we".  One of those
tools is use of your brain for something other than pressing "Send".
David A. Smith
Explain what occurs physically in nature to cause gravity.
Mike Cavedon sez, "I'll say what I want repeatedly and call it correct
as long as you continue to refuse my petty demands to explain
otherwise in a manner than I consider acceptable."
Howzatworkinferya?
"Yes, your statement is a statement about your mind, and your
inability to form a logical argument."
"No, it is not "attraction" in GR, it is that the soil is pushing you
off your force-free orbit."
"Clearly untrue, since you are at least as ignorant of enven Newtonian
physics and logic as the average grade school child."
I'm simply asking the poster, who seems to act as if they have it all
figured out to explain what occurs physically in nature to cause
gravity.
You are not owed that explanation of gravity on usenet even by people
who do understand what is physically going on. That's what I pointed
out when I referred to your "petty demands". If you want to understand
what is physically going on, then read something offline rather than
prattle at people on usenet to explain it to you.
The point you are unable to understand is I understand what occurs
physically in nature to cause gravity.

I am asking the poster to explain what occurs physically in nature to
cause gravity.

Obviously, the following is absurd:

"No, it is not "attraction" in GR, it is that the soil is pushing you
off your force-free orbit."

This means if you are on the opposite side of the Earth's motion you
would fly off the Earth. And what if you are not on the soil? Does
gravity cease to exist?
Post by PD
Post by mpc755
Certainly someone who makes such statements as the poster does and
insists gravity is "the soil pushing you off your force-free orbit"
should be able to explain what is occurring physically in nature to
cause you to be pushed off your force-free orbit.
Yes, and just because he is able does not mean you are entitled to ask
him to produce it on your demand. This is again what I'm referring to
regarding your "petty demands".
Post by mpc755
Unless of course as statement such as the above is simply more
ridiculous absurd nonsense associated with those who think they
understand the physics of nature.
And this statement has to do with my comment about "in a manner I
consider acceptable".
You will find, Mike, that if you ask someone for money and someone
offers you two quarters or a dollar, and you brush it away saying,
"That's not money," and you do that over and over again, pretty soon
you'll discover that your requests for money handouts will result in
people walking right by you. Not because they don't have the money.
But because you're an ass.
If you were at all capable of thinking for yourself you would at least
understand that I am NOT asking for an explanation of what occurs
physically in nature to cause gravity because I already understand
what occurs physically in nature to cause gravity.

Now, obviously, you do not have to understand what occurs physically
in nature to cause gravity.

However, you should at least be able to understand the following is my
correct understanding of what occurs physically in nature to cause
gravity:

Aether has mass.
Aether is displaced by matter.
Displaced aether is not at rest.
Displaced aether exerts force towards matter.
Force exerted towards matter by aether displaced by matter is gravity.
PD
2011-01-26 20:29:47 UTC
Permalink
Post by mpc755
Post by PD
Post by mpc755
Post by PD
Post by mpc755
Post by dlzc
Post by Tim Golden BandTech.com
No. It is not, and a simple argument is enough to
see it. Why has this interpretation become
accepted? Surely this is a statement on the
human mind.
Yes, your statement is a statement about your mind, and your inability
to form a logical argument.
Post by Tim Golden BandTech.com
The argument is constructed simply.
   1. We understand that bodies which are not
under the influence of other bodies will carry on
in a straight path regardless of their relative
velocity.
Neglecting "gravitation" and "charge".
Post by Tim Golden BandTech.com
This is one of Newton's laws which is akin to the
term 'inertia'. I do not challenge this precept and
instead see that the claims of spatial curvature are
not enough to reuse this law in the gravitational
setting.
As has already been said, "spatial curvature" isn't what General
Relativity is about.  The "rubber sheet" analogy is for babies.
Post by Tim Golden BandTech.com
   2. General Relativity claims that the mass of a
body causes spatial curvature,
No, it does not.
Post by Tim Golden BandTech.com
thus altering what to an inertial body would see as
its straight line path. This supposedly explains the
orbits of planetary bodies around the sun as well as
our own attraction to the earth beneath our feet.
No, it is not "attraction" in GR, it is that the soil is pushing you
off your force-free orbit.
Post by Tim Golden BandTech.com
However, the spatial curvature is regarded as a
constant regardless of a body's velocity.
Not "regardless", just a very weak function.  The "energy of motion"
does contribute to local curvature, its just not a lot of "equivalent
mass" until you are moving very fast... and the effects could likely
on be measured over light years.
Post by Tim Golden BandTech.com
This would mean that a high velocity body would
travel the same trajectory as a low velocity body
under the curved space interpretation.
No, it does not.  If you knew Newton as you claim, you'd be aware of
the concept of "impulse".  A constant force over a variable period of
time, results in different trajectories.
Post by Tim Golden BandTech.com
We know that this is not true, and that a body with
greater velocity will travel a different path.  The higher
the body's velocity, the straighter will be its path.
Therefor the space curvature interpretation is suspect.
No, your understanding of even Newtonian physics is suspect.  And
clearly you haven't a clue about Relativity, which you seek to
critique based on your misconceptions.
Post by Tim Golden BandTech.com
   "General relativity is a metric theory of gravitation.
At its core are Einstein's equations, which describe
the relation between the geometry of a four-dimensional,
pseudo-Riemannian manifold representing spacetime,
and the energy-momentum contained in that
spacetime.[31] Phenomena that in classical mechanics
are ascribed to the action of the force of gravity (such as
free-fall, orbital motion, and spacecraft trajectories),
correspond to inertial motion within a curved geometry
of spacetime in general relativity; there is no
gravitational force deflecting objects from their natural,
straight paths. Instead, gravity corresponds to changes
in the properties of space and time,
Note: they are a *set*.
Post by Tim Golden BandTech.com
which in turn changes the straightest-possible paths
that objects will naturally follow.[32] The curvature is,
in turn, caused by the energy-momentum of matter.
Paraphrasing the relativist John Archibald Wheeler,
spacetime tells matter how to move; matter tells
spacetime how to curve.[33]"
 -http://en.wikipedia.org/wiki/General_relativity#Definition_and_basic_...
I believe that the criticism I am harboring goes
beyond the layman's interpretations,
Clearly untrue, since you are at least as ignorant of enven Newtonian
physics and logic as the average grade school child.
<snip the rest of your painfull to see drivel>
...
Post by Tim Golden BandTech.com
Perhaps we are still missing some fundamental tools.
The truth comes out, if *you* are conatined in "we".  One of those
tools is use of your brain for something other than pressing "Send".
David A. Smith
Explain what occurs physically in nature to cause gravity.
Mike Cavedon sez, "I'll say what I want repeatedly and call it correct
as long as you continue to refuse my petty demands to explain
otherwise in a manner than I consider acceptable."
Howzatworkinferya?
"Yes, your statement is a statement about your mind, and your
inability to form a logical argument."
"No, it is not "attraction" in GR, it is that the soil is pushing you
off your force-free orbit."
"Clearly untrue, since you are at least as ignorant of enven Newtonian
physics and logic as the average grade school child."
I'm simply asking the poster, who seems to act as if they have it all
figured out to explain what occurs physically in nature to cause
gravity.
You are not owed that explanation of gravity on usenet even by people
who do understand what is physically going on. That's what I pointed
out when I referred to your "petty demands". If you want to understand
what is physically going on, then read something offline rather than
prattle at people on usenet to explain it to you.
The point you are unable to understand is I understand what occurs
physically in nature to cause gravity.
Not in the way scientists use the word "understand". You think
"understand" means being able to write down plausible-sounding
sentences. Scientists demand that "understand" entails being able to
generate distinct and quantitative predictions that set it apart from
other competing models and which can be tested in measurement.

There's a basic disconnect on vocabulary, Mike.

What you think you have (in terms of understanding) nobody in science
cares about. And what science does care about (in terms of
understanding) you don't have.
Post by mpc755
I am asking the poster to explain what occurs physically in nature to
cause gravity.
"No, it is not "attraction" in GR, it is that the soil is pushing you
off your force-free orbit."
This means if you are on the opposite side of the Earth's motion you
would fly off the Earth.
No it doesn't mean that. Don't be a complete moron.
The air inside a balloon pushes the right-side of the balloon wall to
the right. Does that mean that the air inside the balloon sucks the
left-side of the balloon wall to the right?

Aren't you completely embarrassed when you make goofball statements
like that?
Post by mpc755
And what if you are not on the soil? Does
gravity cease to exist?
Post by PD
Post by mpc755
Certainly someone who makes such statements as the poster does and
insists gravity is "the soil pushing you off your force-free orbit"
should be able to explain what is occurring physically in nature to
cause you to be pushed off your force-free orbit.
Yes, and just because he is able does not mean you are entitled to ask
him to produce it on your demand. This is again what I'm referring to
regarding your "petty demands".
Post by mpc755
Unless of course as statement such as the above is simply more
ridiculous absurd nonsense associated with those who think they
understand the physics of nature.
And this statement has to do with my comment about "in a manner I
consider acceptable".
You will find, Mike, that if you ask someone for money and someone
offers you two quarters or a dollar, and you brush it away saying,
"That's not money," and you do that over and over again, pretty soon
you'll discover that your requests for money handouts will result in
people walking right by you. Not because they don't have the money.
But because you're an ass.
If you were at all capable of thinking for yourself you would at least
understand that I am NOT asking for an explanation of what occurs
physically in nature to cause gravity because I already understand
what occurs physically in nature to cause gravity.
This would explain of course why you keep asking for an explanation of
what occurs physically in nature to cause gravity.

Ah of course! You ask for something not because you want it but
because you already have it!

There's only one thing more spectacular than a buffoon and that's a
buffoon dressed in clown clothes who sets himself on fire and jumps in
front of a train.
Post by mpc755
Now, obviously, you do not have to understand what occurs physically
in nature to cause gravity.
However, you should at least be able to understand the following is my
correct understanding of what occurs physically in nature to cause
Aether has mass.
Aether is displaced by matter.
Displaced aether is not at rest.
Displaced aether exerts force towards matter.
Force exerted towards matter by aether displaced by matter is gravity.
mpc755
2011-01-26 20:38:48 UTC
Permalink
Post by PD
What you think you have (in terms of understanding) nobody in science
cares about.
And that is why you are incapable of understanding the following:

Aether has mass.
Aether is displaced by matter.
Displaced aether is not at rest.
Displaced aether exerts force towards matter.
Force exerted towards matter by aether displaced by matter is gravity.
PD
2011-01-26 20:40:17 UTC
Permalink
Post by mpc755
Post by PD
What you think you have (in terms of understanding) nobody in science
cares about.
Aether has mass.
Aether is displaced by matter.
Displaced aether is not at rest.
Displaced aether exerts force towards matter.
Force exerted towards matter by aether displaced by matter is gravity.
That's fine. You have a product to sell that no one is interested in
buying. When that happens to an inventor or a salesman, whose fault is
it for the failure?
mpc755
2011-01-26 20:46:02 UTC
Permalink
Post by PD
Post by mpc755
Post by PD
What you think you have (in terms of understanding) nobody in science
cares about.
Aether has mass.
Aether is displaced by matter.
Displaced aether is not at rest.
Displaced aether exerts force towards matter.
Force exerted towards matter by aether displaced by matter is gravity.
That's fine. You have a product to sell that no one is interested in
buying. When that happens to an inventor or a salesman, whose fault is
it for the failure?
The fault is in your inability to understand anything that wasn't
professed to you.

The galaxy clusters in the following article are not traveling with
dark matter. The galaxy clusters are moving through the aether. The
galaxy clusters displace aether.

'Hubble Finds Ghostly Ring of Dark Matter'
http://www.nasa.gov/mission_pages/hubble/news/dark_matter_ring_feature.html

"Astronomers using NASA's Hubble Space Telescope got a first-hand view
of how dark matter behaves during a titanic collision between two
galaxy clusters. The wreck created a ripple of dark mater, which is
somewhat similar to a ripple formed in a pond when a rock hits the
water."

The 'pond' consists of aether.
The moving 'particles' are the galaxy clusters.
The 'ripple' is an aether displacement wave.
PD
2011-01-26 21:03:08 UTC
Permalink
Post by mpc755
Post by PD
Post by mpc755
Post by PD
What you think you have (in terms of understanding) nobody in science
cares about.
Aether has mass.
Aether is displaced by matter.
Displaced aether is not at rest.
Displaced aether exerts force towards matter.
Force exerted towards matter by aether displaced by matter is gravity.
That's fine. You have a product to sell that no one is interested in
buying. When that happens to an inventor or a salesman, whose fault is
it for the failure?
The fault is in your inability to understand anything that wasn't
professed to you.
You just keep telling yourself that, Mike. I'm sure it's good to
protect your ego that way.
I'm sure there are many inventors and salesman who blame their
customers for not wanting what they have to offer. Anything to keep
from facing facts.
mpc755
2011-01-26 21:15:05 UTC
Permalink
Post by PD
Post by mpc755
Post by PD
Post by mpc755
Post by PD
What you think you have (in terms of understanding) nobody in science
cares about.
Aether has mass.
Aether is displaced by matter.
Displaced aether is not at rest.
Displaced aether exerts force towards matter.
Force exerted towards matter by aether displaced by matter is gravity.
That's fine. You have a product to sell that no one is interested in
buying. When that happens to an inventor or a salesman, whose fault is
it for the failure?
The fault is in your inability to understand anything that wasn't
professed to you.
You just keep telling yourself that, Mike. I'm sure it's good to
protect your ego that way.
I'm sure there are many inventors and salesman who blame their
customers for not wanting what they have to offer. Anything to keep
from facing facts.
The fact is the galaxy clusters in the following are not traveling
with dark matter. The fact is the galaxy clusters are traveling
through the aether.

Keeping from facing facts is something you are an expert in.

The galaxy clusters in the following article are not traveling with
dark matter. The galaxy clusters are moving through the aether. The
galaxy clusters displace aether.

'Hubble Finds Ghostly Ring of Dark Matter'
http://www.nasa.gov/mission_pages/hubble/news/dark_matter_ring_feature.html

"Astronomers using NASA's Hubble Space Telescope got a first-hand view
of how dark matter behaves during a titanic collision between two
galaxy clusters. The wreck created a ripple of dark mater, which is
somewhat similar to a ripple formed in a pond when a rock hits the
water."

The 'pond' consists of aether.
The moving 'particles' are the galaxy clusters.
The 'ripple' is an aether displacement wave.
PD
2011-01-26 21:56:50 UTC
Permalink
Post by mpc755
Post by PD
Post by mpc755
Post by PD
Post by mpc755
Post by PD
What you think you have (in terms of understanding) nobody in science
cares about.
Aether has mass.
Aether is displaced by matter.
Displaced aether is not at rest.
Displaced aether exerts force towards matter.
Force exerted towards matter by aether displaced by matter is gravity.
That's fine. You have a product to sell that no one is interested in
buying. When that happens to an inventor or a salesman, whose fault is
it for the failure?
The fault is in your inability to understand anything that wasn't
professed to you.
You just keep telling yourself that, Mike. I'm sure it's good to
protect your ego that way.
I'm sure there are many inventors and salesman who blame their
customers for not wanting what they have to offer. Anything to keep
from facing facts.
The fact is the galaxy clusters in the following are not traveling
with dark matter. The fact is the galaxy clusters are traveling
through the aether.
Keeping from facing facts is something you are an expert in.
Well, again, there is a problem of vocabulary here. What you call
"fact" is what scientists would call "conjecture". So as long as there
is disagreement on what "understand" and "fact" mean, among a few
other things, you'll not get very far.

Note that you have not managed to get one person to buy into what
you're saying. Not one.

You'll notice that having the last word does not improve that
statistic. The reason is that you're being an ass.
Post by mpc755
The galaxy clusters in the following article are not traveling with
dark matter. The galaxy clusters are moving through the aether. The
galaxy clusters displace aether.
'Hubble Finds Ghostly Ring of Dark Matter'http://www.nasa.gov/mission_pages/hubble/news/dark_matter_ring_featur...
"Astronomers using NASA's Hubble Space Telescope got a first-hand view
of how dark matter behaves during a titanic collision between two
galaxy clusters. The wreck created a ripple of dark mater, which is
somewhat similar to a ripple formed in a pond when a rock hits the
water."
The 'pond' consists of aether.
The moving 'particles' are the galaxy clusters.
The 'ripple' is an aether displacement wave.
mpc755
2011-01-26 22:03:22 UTC
Permalink
Post by PD
Well, again, there is a problem of vocabulary here. What you call
"fact" is what scientists would call "conjecture". So as long as there
is disagreement on what "understand" and "fact" mean, among a few
other things, you'll not get very far.
Note that you have not managed to get one person to buy into what
you're saying. Not one.
You'll notice that having the last word does not improve that
statistic. The reason is that you're being an ass.
The galaxy clusters in the following article are not traveling with
dark matter. The galaxy clusters are moving through the aether. The
galaxy clusters displace aether.

'Hubble Finds Ghostly Ring of Dark Matter'
http://www.nasa.gov/mission_pages/hubble/news/dark_matter_ring_feature.html

"Astronomers using NASA's Hubble Space Telescope got a first-hand view
of how dark matter behaves during a titanic collision between two
galaxy clusters. The wreck created a ripple of dark mater, which is
somewhat similar to a ripple formed in a pond when a rock hits the
water."

The 'pond' consists of aether.
The moving 'particles' are the galaxy clusters.
The 'ripple' is an aether displacement wave.

Dark matter IS aether.
Aether has mass.
Aether is displaced by matter.
Displaced aether is not at rest.
Displaced aether exerts force towards matter.
Force exerted towards matter by aether displaced by matter is gravity.

Now, when I ask you to explain what occurs physically in nature to
cause gravity, I am asking you because I already know you can't
answer.

Gravity is the force exerted by displaced aether towards matter.
spudnik
2011-01-28 02:37:58 UTC
Permalink
have teh last word, again, aetherdood.

incidentally, Gauss measured the local curvature
of space in the 19th cce, Alsace Lorraine,
paid by the French Goment. also,
Eratosthenes, somewhat more famously,
corresponding with a friend at another lattitude,
another gnomon.
mpc755
2011-01-28 03:46:13 UTC
Permalink
Post by spudnik
have teh last word, again, aetherdood.
incidentally, Gauss measured the local curvature
of space in the 19th cce, Alsace Lorraine,
paid by the French Goment.  also,
Eratosthenes, somewhat more famously,
corresponding with a friend at another lattitude,
another gnomon.
Curved spacetime is displaced aether.

The rate at which an atomic clock ticks is determined by the force of
the aether in which it exists.
RichD
2011-01-31 18:19:54 UTC
Permalink
Dear David A. Smith,
Post by Tim Golden BandTech.com
Perhaps we are still missing some fundamental tools.
The truth comes out, if *you* are conatined in "we". > One of those tools is use of your brain for
something other than pressing "Send".
He thinks with his heart.

--
Rich
Eric Gisse
2011-01-26 16:30:02 UTC
Permalink
Post by Tim Golden BandTech.com
No. It is not, and a simple argument is enough to see it. Why has this
interpretation become accepted?
It makes correct predictions. That is all that is required.
Post by Tim Golden BandTech.com
Surely this is a statement on the
human mind.
The argument is constructed simply.
   1. We understand that bodies which are not under the influence of
other bodies will carry on in a straight path regardless of their
relative velocity. This is one of Newton's laws which is akin to the
term 'inertia'. I do not challenge this precept and instead see that
the claims of spatial curvature are not enough to reuse this law in
the gravitational setting.
   2. General Relativity claims that the mass of a body causes spatial
curvature, thus altering what to an inertial body would see as its
straight line path. This supposedly explains the orbits of planetary
bodies around the sun as well as our own attraction to the earth
beneath our feet. However, the spatial curvature is regarded as a
constant regardless of a body's velocity. This would mean that a high
velocity body would travel the same trajectory as a low velocity body
under the curved space interpretation. We know that this is not true,
What you say is simply incorrect. Curvature is not at all regarded as
a "constant", nor should two different bodies with different
velocities move along the same trajectory through spacetime. That's
not even true when there is no curvature.

[...]
Post by Tim Golden BandTech.com
I believe that the criticism I am harboring goes beyond the layman's
interpretations, for here is a fairly technical interpretation which
still has blatant disregard for velocity. This means that if we were
to accelerate the earth in its course that it would hold course in its
current orbit.
No, it does not.

[...]
PD
2011-01-26 18:08:19 UTC
Permalink
Post by Tim Golden BandTech.com
No. It is not, and a simple argument is enough to see it. Why has this
interpretation become accepted? Surely this is a statement on the
human mind.
The argument is constructed simply.
   1. We understand that bodies which are not under the influence of
other bodies will carry on in a straight path regardless of their
relative velocity. This is one of Newton's laws which is akin to the
term 'inertia'. I do not challenge this precept and instead see that
the claims of spatial curvature are not enough to reuse this law in
the gravitational setting.
   2. General Relativity claims that the mass of a body causes spatial
curvature, thus altering what to an inertial body would see as its
straight line path. This supposedly explains the orbits of planetary
bodies around the sun as well as our own attraction to the earth
beneath our feet. However, the spatial curvature is regarded as a
constant regardless of a body's velocity.
The entire argument of this posts rests on this error. The curvature
you mention is *spacetime* curvature, not spatial curvature. It is a
fairly straightforward exercise to show that objects with different
velocities in the same curved *spacetime* will execute different
trajectories. Hint: Look at what different velocities express
themselves as on a spacetime diagram.
Post by Tim Golden BandTech.com
This would mean that a high
velocity body would travel the same trajectory as a low velocity body
under the curved space interpretation. We know that this is not true,
and that a body with greater velocity will travel a different path.
The higher the body's velocity, the straighter will be its path.
Therefor the space curvature interpretation is suspect.
   "General relativity is a metric theory of gravitation. At its core
are Einstein's equations, which describe the relation between the
geometry of a four-dimensional, pseudo-Riemannian manifold
representing spacetime, and the energy-momentum contained in that
spacetime.[31] Phenomena that in classical mechanics are ascribed to
the action of the force of gravity (such as free-fall, orbital motion,
and spacecraft trajectories), correspond to inertial motion within a
curved geometry of spacetime in general relativity; there is no
gravitational force deflecting objects from their natural, straight
paths. Instead, gravity corresponds to changes in the properties of
space and time, which in turn changes the straightest-possible paths
that objects will naturally follow.[32] The curvature is, in turn,
caused by the energy-momentum of matter. Paraphrasing the relativist
John Archibald Wheeler, spacetime tells matter how to move; matter
tells spacetime how to curve.[33]"
 -http://en.wikipedia.org/wiki/General_relativity#Definition_and_basic_...
I believe that the criticism I am harboring goes beyond the layman's
interpretations, for here is a fairly technical interpretation which
still has blatant disregard for velocity. This means that if we were
to accelerate the earth in its course that it would hold course in its
current orbit. This is a false statement and corrections should be
made. Whether the corrections are in my own interpretation of the
above information, well, I am open to that. Still, I am likewise open
to corrections being made in the numerous texts that exist on the
other side of the supposed conflict. If I am correct then this is one
more stage of support for the stupidity of humanity. Still, even if we
are stupid, we have to work with what we've got. This means keeping
things simple, and I believe that the simplicity of my own argument
      If space is curved, then the force free paths ('straight')
through that curved space
      have no dependence upon an object's velocity along those paths.
This statement essentially challenges the construction of curved
space, but I do not need to go this far in order to launch the
criticism. Please note that the defense of relativity theory by
experiment does not void this criticism. The curve fitters paradigm is
not pure theory. Here if I have to extend my criticism it is that the
theory requires revision in order to come clean, and that somehow
working with the tools that were available Einstein (and others)
managed to do quite well, but perhaps the models running in his head
were even cleaner than those that he was able to pen. Perhaps we are
still missing some fundamental tools.
 - Tim
Tom Roberts
2011-01-26 18:50:15 UTC
Permalink
Post by Tim Golden BandTech.com
No. It is not, and a simple argument is enough to see it.
Your argument is COMPLETELY flawed. So much so that it is useless.
Post by Tim Golden BandTech.com
Why has this
interpretation become accepted? Surely this is a statement on the
human mind.
No. It is a statement about the validity of General Relativity as a theory of
physics.
Post by Tim Golden BandTech.com
2. General Relativity claims that the mass of a body causes spatial
curvature, thus altering what to an inertial body would see as its
straight line path.
This is so incomplete that it is tantamount to being wrong. It is spaceTIME
curvature that is important. In the vicinity of the earth, the spatial curvature
is negligible, but the curvature of spacetime explains all falling and orbiting
objects to high accuracy, as well as the forces on objects supported against
gravity.
Post by Tim Golden BandTech.com
This supposedly explains the orbits of planetary
bodies around the sun as well as our own attraction to the earth
beneath our feet.
Yes, it does. But only when one considers the ACTUAL THEORY, and not the
silliness you are trying to discuss.
Post by Tim Golden BandTech.com
However, the spatial curvature is regarded as a
constant regardless of a body's velocity.
Hmmm. Yes the spatial curvature due to the earth, and the spacetime curvature
due to the earth, are independent of the velocity of a thrown baseball. This in
no way implies that the trajectory of the baseball is independent of its initial
velocity -- indeed the trajectory depends STRONGLY on its initial velocity (as
any baseball player will attest).
Post by Tim Golden BandTech.com
[... more nonsense]
You do not know enough about GR to make any statements about it. Your entire
post is just plain wrong. You need to STUDY modern physics, not attempt to
criticize it.


Tom Roberts
mpc755
2011-01-26 18:55:50 UTC
Permalink
Post by Tom Roberts
Post by Tim Golden BandTech.com
No. It is not, and a simple argument is enough to see it.
Your argument is COMPLETELY flawed. So much so that it is useless.
Post by Tim Golden BandTech.com
Why has this
interpretation become accepted? Surely this is a statement on the
human mind.
No. It is a statement about the validity of General Relativity as a theory of
physics.
Post by Tim Golden BandTech.com
    2. General Relativity claims that the mass of a body causes spatial
curvature, thus altering what to an inertial body would see as its
straight line path.
This is so incomplete that it is tantamount to being wrong. It is spaceTIME
curvature that is important. In the vicinity of the earth, the spatial curvature
is negligible, but the curvature of spacetime explains all falling and orbiting
objects to high accuracy, as well as the forces on objects supported against
gravity.
Post by Tim Golden BandTech.com
This supposedly explains the orbits of planetary
bodies around the sun as well as our own attraction to the earth
beneath our feet.
Yes, it does. But only when one considers the ACTUAL THEORY, and not the
silliness you are trying to discuss.
Post by Tim Golden BandTech.com
However, the spatial curvature is regarded as a
constant regardless of a body's velocity.
Hmmm. Yes the spatial curvature due to the earth, and the spacetime curvature
due to the earth, are independent of the velocity of a thrown baseball. This in
no way implies that the trajectory of the baseball is independent of its initial
velocity -- indeed the trajectory depends STRONGLY on its initial velocity (as
any baseball player will attest).
 > [... more nonsense]
You do not know enough about GR to make any statements about it. Your entire
post is just plain wrong. You need to STUDY modern physics, not attempt to
criticize it.
Tom Roberts
SpaceTIME curvature is displaced aether.

The rate at which an atomic clock ticks is determined by the force of
the aether in which it exists.

Force exerted towards matter by aether displaced by matter is gravity.
Koobee Wublee
2011-01-26 18:54:25 UTC
Permalink
Post by Tim Golden BandTech.com
General Relativity claims that the mass of a body causes spatial
curvature, thus altering what to an inertial body would see as its
straight line path.
Gauss was the first to see a curved space. Riemann was the first to
mathematically model curved space. Riemann was also the first to
suggest a connection of gravitation and curved space but failed to
find any connection. If Riemann were to be born a few decades later,
he would no doubt find the connection in curved space and time.
<shrug>

So, yes, spatial curvature alone does not result in gravitation. You
only need curved time or gravitational time dilation. Thus, the
following spacetime is the simplest form that degenerates into
Newtonian law of gravity. <shrug>

ds^2 = c^2 (1 – 2 U) dt^2 – dr^2 – r^2 dO^2

Where

** U = G M / c^2 / r
** dO^2 = dLatitude^2 + cos^2(Latitude) dLongitude^2

Of course, the metric above would not satisfy the man-made Ricci
tensor in free space, and the Schwarzschild metric is not the only one
that degenerates into Newtonian law of gravity either. What else is
new? <shrug>
Alen
2011-01-28 09:22:45 UTC
Permalink
Post by Tim Golden BandTech.com
General Relativity claims that the mass of a body causes spatial
curvature, thus altering what to an inertial body would see as its
straight line path.
Gauss was the first to see a curved space.  Riemann was the first to
mathematically model curved space.  Riemann was also the first to
suggest a connection of gravitation and curved space but failed to
find any connection.  If Riemann were to be born a few decades later,
he would no doubt find the connection in curved space and time.
<shrug>
So, yes, spatial curvature alone does not result in gravitation.  You
only need curved time or gravitational time dilation.  Thus, the
following spacetime is the simplest form that degenerates into
Newtonian law of gravity.  <shrug>
ds^2 = c^2 (1 – 2 U) dt^2 – dr^2 – r^2 dO^2
Where
**  U = G M / c^2 / r
**  dO^2 = dLatitude^2 + cos^2(Latitude) dLongitude^2
Of course, the metric above would not satisfy the man-made Ricci
tensor in free space, and the Schwarzschild metric is not the only one
that degenerates into Newtonian law of gravity either.  What else is
new?  <shrug>
Yes, there have been other attempts besides those
of GR to model gravity, which I find interesting. I like
to ask the question: how can one prove that a small
test object is moving along the geodesic of a spacetime
curved by a large object in whose field it is moving?

The test object, and the above equation, and the
Schwarzschild equation are local only. They don't prove
the existence of a global field.

Therefore, is there anything that can prove that the local
manifold is not merely something being temporarily created
by the interaction of the test object with the other field,
which doesn't otherwise exist as a manifold? Surely we
only infer the existence of a global manifold by observing
localised tests of it!? Is it not true that we can never have
a global view of a gravitational manifold around a massive
body, and can't prove that it even exists in the absence of
a test object?

Alen
Tim Golden BandTech.com
2011-01-28 15:28:01 UTC
Permalink
Post by Alen
Post by Tim Golden BandTech.com
General Relativity claims that the mass of a body causes spatial
curvature, thus altering what to an inertial body would see as its
straight line path.
Gauss was the first to see a curved space.  Riemann was the first to
mathematically model curved space.  Riemann was also the first to
suggest a connection of gravitation and curved space but failed to
find any connection.  If Riemann were to be born a few decades later,
he would no doubt find the connection in curved space and time.
<shrug>
So, yes, spatial curvature alone does not result in gravitation.  You
only need curved time or gravitational time dilation.  Thus, the
following spacetime is the simplest form that degenerates into
Newtonian law of gravity.  <shrug>
ds^2 = c^2 (1 – 2 U) dt^2 – dr^2 – r^2 dO^2
Where
**  U = G M / c^2 / r
**  dO^2 = dLatitude^2 + cos^2(Latitude) dLongitude^2
Of course, the metric above would not satisfy the man-made Ricci
tensor in free space, and the Schwarzschild metric is not the only one
that degenerates into Newtonian law of gravity either.  What else is
new?  <shrug>
Yes, there have been other attempts besides those
of GR to model gravity, which I find interesting. I like
to ask the question: how can one prove that a small
test object is moving along the geodesic of a spacetime
curved by a large object in whose field it is moving?
The test object, and the above equation, and the
Schwarzschild equation are local only. They don't prove
the existence of a global field.
Therefore, is there anything that can prove that the local
manifold is not merely something being temporarily created
by the interaction of the test object with the other field,
which doesn't otherwise exist as a manifold? Surely we
only infer the existence of a global manifold by observing
localised tests of it!? Is it not true that we can never have
a global view of a gravitational manifold around a massive
body, and can't prove that it even exists in the absence of
a test object?
Alen
Hi Alen. Neat perspective. There is actually a logical problem with a
reliance upon a local reference frame that is fundamental. The literal
requirement of a local reference frame is to constrain to the
neighborhood of a position, and so long as no finite range is
specified the constraint is infinitesimal. Sadly, at this local range,
what we see is that stable matter breaks down and charged particles
with spin characteristics are what are accepted to exist in modernity,
with tremendous dynamics down at that level. The requirement of the
'local reference frame' is essentially an admission that no general
application is possible, for the results are too limited to provide
any results. I see that you are aware of this. Let's try to extend
this criticism as strongly as possible, and preferably without
starting a food fight. Of course what we'd really like is a
replacement theory, but often it is by clean criticism of an existing
theory that one arrives nearby to a new theory. I understand that the
experimental factors are in support of GR, and this is a fascinating
feature. This could mean that AE had a cleaner model in his mind than
he was able to express in the existing language. In other words there
may be fundamental mathematics which has not yet been constructed by
humans, or at least not yet cleanly expressed. Still I am open to
being falsified on the crux here, but the simplicity of the
interpretation will have to be struck by the falsifier.

- Tim
dlzc
2011-01-28 16:08:42 UTC
Permalink
Dear Alen:

On Jan 28, 2:22 am, Alen <***@westserv.net.au> wrote:
...
Post by Alen
Yes, there have been other attempts besides those
of GR to model gravity, which I find interesting. I like
to ask the question: how can one prove that a small
test object is moving along the geodesic of a spacetime
curved by a large object in whose field it is moving?
The test object, and the above equation, and the
Schwarzschild equation are local only. They don't
prove the existence of a global field.
No proofs in Science, remember. What would be something we could
test?
Post by Alen
Therefore, is there anything that can prove that the
local manifold is not merely something being
temporarily created by the interaction of the test
object with the other field, which doesn't otherwise
exist as a manifold?
Does light count as a "test object"? If not (it has no rest mass),
how about gravitational lensing? This occurs even in sparsely
populated space...
Post by Alen
Surely we only infer the existence of a global
manifold by observing localised tests of it!?
Binding of superclusters. Rotation curves of spiral galaxies. Not
saying GR does all this right, but it looks pretty continuous. I
think the break occurs in the local, and not in the large. I think
the manifold is a "population feature", that is not present locally.
Post by Alen
Is it not true that we can never have a global
view of a gravitational manifold around a massive
body, and can't prove that it even exists in the
absence of a test object?
Science is about testing. If you cannot test it, if when you do test
it the manifold is present, isn't it simpler to assume that
instantaneous signalling is not required to establish the manifold to
the right values?

David A. Smith
Tim Golden BandTech.com
2011-01-28 19:27:55 UTC
Permalink
Science is about testing.  If you cannot test it, if when you do test
it the manifold is present, isn't it simpler to assume that
instantaneous signalling is not required to establish the manifold to
the right values?
David A. Smith
This is only partially accurate. When we present a theory about an
observed behavior then we are looking for more than an arithmetic
match. This level of correspondence I call the curve fitter's
paradigm. That Einstein's theory predicted behaviors is true, but this
does not mean that the theory cannot be improved. I have already at
the outset made this sort of statement. We are discussing theoretical
physics now. I cannot invalidate your perspective, but I can point out
this other perspective, which is not the experimental paradigm. Yes,
the two should go hand in hand, but let's not mistake the left hand
for the right hand, or the wrong hand.

You might as well argue that theories which are incoherent are
acceptable so long as they obey the experimental observations. This is
nearly where quantum mechanics is at now. We would like to break
through to a new cleaner understanding of these things. That some new
fairly parallel theory may exist is somewhat why we all study these
topics, presuming that we would like to make contributions to the
state of the art. That we are caught in a progression is pretty clear.
That these areas of progress are very difficult for humans is likewise
clear. One way through is to attempt falsification of what has come
before, and upon validating such a weakness in the old theory then
there is room made for the new theory.

Alen, I found your site from some of your previous posts
http://www.google.com/url?sa=D&q=http://www.alenspage.net/Geodesic.htm
and am reading along and see that we are up the same alley. I don't
mean to overestimate our agreement, but I have likewise pondered the
observability of curved space, or curved spacetime. So long as we are
going to maintain purity we should admit that the observance of three
dimensional space is an experimental fact and that until a theory
arrives which derives those three dimensions, and unidirectional time,
then theory is lacking. I happen to have some pure math that makes
progress on this front.

- Tim
PD
2011-01-28 19:36:23 UTC
Permalink
Post by Tim Golden BandTech.com
Science is about testing.  If you cannot test it, if when you do test
it the manifold is present, isn't it simpler to assume that
instantaneous signalling is not required to establish the manifold to
the right values?
David A. Smith
This is only partially accurate. When we present a theory about an
observed behavior then we are looking for more than an arithmetic
match. This level of correspondence I call the curve fitter's
paradigm. That Einstein's theory predicted behaviors is true, but this
does not mean that the theory cannot be improved. I have already at
the outset made this sort of statement. We are discussing theoretical
physics now. I cannot invalidate your perspective, but I can point out
this other perspective, which is not the experimental paradigm. Yes,
the two should go hand in hand, but let's not mistake the left hand
for the right hand, or the wrong hand.
Tim, this is off base.

Curve-fitting is building a model that fits *currently* known data,
but makes no fundamentally new predictions other than what can be
drawn from the curve.

A scientific theory is different in that it makes new and distinctive
predictions that can be tested. That is the SOLE measure.
Post by Tim Golden BandTech.com
You might as well argue that theories which are incoherent are
acceptable so long as they obey the experimental observations. This is
nearly where quantum mechanics is at now. We would like to break
through to a new cleaner understanding of these things.
Incoherence is only a mismatch with a previously held concept-set.
What you are aspiring to is a way to model things in a manner that
retains the previous concept-set, presumably including things like
strict, time-ordered, causal determinism.

What a new theory often demands is that a *new* concept-set is
generated. This often means new meanings of words, or new words
entirely, to describe these new concepts. This revised conceptual
understanding often comes after the match to experimental observations
is established, but it DOES happen.

Those who continue to struggle with incomprehension of century-old
ideas are usually the ones who are clinging mighty hard to old concept
sets.
Post by Tim Golden BandTech.com
That some new
fairly parallel theory may exist is somewhat why we all study these
topics, presuming that we would like to make contributions to the
state of the art. That we are caught in a progression is pretty clear.
That these areas of progress are very difficult for humans is likewise
clear. One way through is to attempt falsification of what has come
before, and upon validating such a weakness in the old theory then
there is room made for the new theory.
Alen, I found your site from some of your previous posts
   http://www.google.com/url?sa=D&q=http://www.alenspage.net/Geodesic.htm
and am reading along and see that we are up the same alley. I don't
mean to overestimate our agreement, but I have likewise pondered the
observability of curved space, or curved spacetime. So long as we are
going to maintain purity we should admit that the observance of three
dimensional space is an experimental fact and that until a theory
arrives which derives those three dimensions, and unidirectional time,
then theory is lacking. I happen to have some pure math that makes
progress on this front.
 - Tim
Odysseus
2011-01-29 03:03:58 UTC
Permalink
In article
<956feaf3-57f1-4453-91c1-***@8g2000prb.googlegroups.com>,
PD <***@gmail.com> wrote:

<snip>
Post by PD
Curve-fitting is building a model that fits *currently* known data,
but makes no fundamentally new predictions other than what can be
drawn from the curve.
A scientific theory is different in that it makes new and distinctive
predictions that can be tested. That is the SOLE measure.
OTOH a theory can be motivated by the results of curve-fitting or other
aids to pattern-detection. As the theory matures, hypotheses & ad-hoc
constructs are replaced by generalizations & models with observable
consequences that can be deduced & predicted. Nonetheless, I'm sure many
a curve-fitting exercise has sparked an important new idea in some
scientist's brain.
--
Odysseus
spudnik
2011-01-29 03:47:18 UTC
Permalink
of course, if one has a new hypothesis,
it might generate a better-fit curve ...
of at least two variables?

BandTech never says a God-am thing, though;
nor mpc#bot.
Alen
2011-01-29 03:22:39 UTC
Permalink
...
Post by Alen
Yes, there have been other attempts besides those
of GR to model gravity, which I find interesting. I like
to ask the question: how can one prove that a small
test object is moving along the geodesic of a spacetime
curved by a large object in whose field it is moving?
The test object, and the above equation, and the
Schwarzschild equation are local only. They don't
prove the existence of a global field.
No proofs in Science, remember.  What would be something we could
test?
Post by Alen
Therefore, is there anything that can prove that the
local manifold is not merely something being
temporarily created by the interaction of the test
object with the other field, which doesn't otherwise
exist as a manifold?
Does light count as a "test object"?  If not (it has no rest mass),
how about gravitational lensing?  This occurs even in sparsely
populated space...
I don't see why light shouldn't be counted
as a test object. It has no rest mass, yes, but
don't we say that its energy has mass equivalence?
Post by Alen
Surely we only infer the existence of a global
manifold by observing localised tests of it!?
Binding of superclusters.  Rotation curves of spiral galaxies.  Not
saying GR does all this right, but it looks pretty continuous.  I
think the break occurs in the local, and not in the large.  I think
the manifold is a "population feature", that is not present locally.
Certainly you will have a continuous effect if there
are so many 'test objects' (incl. light) that they are effectively
'testing' the entire field, or manifold, at the same time.
It still doesn't establish that the manifold is not
basically a temporary creation of such objects,
in conjunction with the field of the massive body.
Post by Alen
Is it not true that we can never have a global
view of a gravitational manifold around a massive
body, and can't prove that it even exists in the
absence of a test object?
Science is about testing.  If you cannot test it, if when you do test
it the manifold is present, isn't it simpler to assume that
instantaneous signalling is not required to establish the manifold to
the right values?
David A. Smith
Would instantaneous signalling be necessary
if a field was distributed in space, just like the
manifold is assumed to be?

Alen
dlzc
2011-01-30 16:56:04 UTC
Permalink
Post by Alen
...
Post by Alen
Yes, there have been other attempts besides
those of GR to model gravity, which I find
how can one prove that a small test object
is moving along the geodesic of a spacetime
curved by a large object in whose field it
is moving?
The test object, and the above equation, and
the Schwarzschild equation are local only.
They don't prove the existence of a global
field.
No proofs in Science, remember.  What would
be something we could test?
Post by Alen
Therefore, is there anything that can prove
that the local manifold is not merely
something being temporarily created by the
interaction of the test object with the
other field, which doesn't otherwise exist
as a manifold?
Does light count as a "test object"?  If not
(it has no rest mass), how about gravitational
lensing?  This occurs even in sparsely
populated space...
I don't see why light shouldn't be counted
as a test object. It has no rest mass, yes, but
don't we say that its energy has mass equivalence?
Sure. However light follows a path through curved spacetime that not
even the fastest material particle approaches even asymptotically.
Post by Alen
Post by Alen
Surely we only infer the existence of a global
manifold by observing localised tests of it!?
Binding of superclusters.  Rotation curves of
spiral galaxies.  Not saying GR does all this
right, but it looks pretty continuous.  I think
the break occurs in the local, and not in the
large.  I think the manifold is a "population
feature", that is not present locally.
Certainly you will have a continuous effect if
there are so many 'test objects' (incl. light)
that they are effectively 'testing' the entire
field, or manifold, at the same time. It still
doesn't establish that the manifold is not
basically a temporary creation of such objects,
in conjunction with the field of the massive body.
Granted. Now if there is no way to test the manifold, that does not
in fact produce it... and to do so requires instantaneous signaling...

We cannot know about Reality, except via measurement. Measurement
yields manifold.
Post by Alen
Post by Alen
Is it not true that we can never have a
global view of a gravitational manifold
around a massive body, and can't prove that
it even exists in the absence of a test
object?
Science is about testing.  If you cannot
test it, if when you do test it the manifold
is present, isn't it simpler to assume that
instantaneous [signaling] is not required to
establish the manifold to the right values?
Would instantaneous [signaling] be necessary
if a field was distributed in space, just like the
manifold is assumed to be?
Yes. If what was supposed to be present in a "region of space" was
"forgotten" between "tests", then how does it get properly, uniformly
established at each of a series positions? If there is not
"something" at each place, then instantaneous signaling must carry
distance and mass-contribution values between the two objects. If it
were not instantaneous, then gravitation would fall off by more than 1/
r^2.

David A. Smith
Alen
2011-01-31 02:49:28 UTC
Permalink
Post by Alen
...
Post by Alen
Yes, there have been other attempts besides
those of GR to model gravity, which I find
how can one prove that a small test object
is moving along the geodesic of a spacetime
curved by a large object in whose field it
is moving?
The test object, and the above equation, and
the Schwarzschild equation are local only.
They don't prove the existence of a global
field.
No proofs in Science, remember.  What would
be something we could test?
Post by Alen
Therefore, is there anything that can prove
that the local manifold is not merely
something being temporarily created by the
interaction of the test object with the
other field, which doesn't otherwise exist
as a manifold?
Does light count as a "test object"?  If not
(it has no rest mass), how about gravitational
lensing?  This occurs even in sparsely
populated space...
I don't see why light shouldn't be counted
as a test object. It has no rest mass, yes, but
don't we say that its energy has mass equivalence?
Sure.  However light follows a path through curved spacetime that not
even the fastest material particle approaches even asymptotically.
Post by Alen
Post by Alen
Surely we only infer the existence of a global
manifold by observing localised tests of it!?
Binding of superclusters.  Rotation curves of
spiral galaxies.  Not saying GR does all this
right, but it looks pretty continuous.  I think
the break occurs in the local, and not in the
large.  I think the manifold is a "population
feature", that is not present locally.
Certainly you will have a continuous effect if
there are so many 'test objects' (incl. light)
that they are effectively 'testing' the entire
field, or manifold, at the same time.  It still
doesn't establish that the manifold is not
basically a temporary creation of such objects,
in conjunction with the field of the massive body.
Granted.  Now if there is no way to test the manifold, that does not
in fact produce it... and to do so requires instantaneous signaling...
We cannot know about Reality, except via measurement.  Measurement
yields manifold.
Post by Alen
Post by Alen
Is it not true that we can never have a
global view of a gravitational manifold
around a massive body, and can't prove that
it even exists in the absence of a test
object?
Science is about testing.  If you cannot
test it, if when you do test it the manifold
is present, isn't it simpler to assume that
instantaneous [signaling] is not required to
establish the manifold to the right values?
Would instantaneous [signaling] be necessary
if a field was distributed in space, just like the
manifold is assumed to be?
Yes.  If what was supposed to be present in a "region of space" was
"forgotten" between "tests", then how does it get properly, uniformly
established at each of a series positions?  If there is not
"something" at each place, then instantaneous signaling must carry
distance and mass-contribution values between the two objects.  If it
were not instantaneous, then gravitation would fall off by more than 1/
r^2.
David A. Smith
I don't understand this instantaneous signalling necessity.
If there is nothing distributed in space, then the objects
won't even know of one another's existence, unless they
are sending signals at all times, which would be problematic.
If, however, both have 'fields' distributed in flat spacetime,
these fields will interfere with one another as they come into
contact. I don't see why these fields might not together
create the equivalent of a 'surface', of limited extent, along
which the trajectory is a geodesic. As the objects relatively
move, they continuously create the surface within which the
relative motion exists. One could visualise this process in a
stepwise kind of way, if necessary. Whether this is the best
description, or not, I don't see why interaction of distributed
fields with one another requires signalling between the centres
of mass themselves??

Alen
dlzc
2011-01-31 13:55:06 UTC
Permalink
Dear Alen:

On Jan 30, 7:49 pm, Alen <***@westserv.net.au> wrote:
...
Post by Alen
I don't understand this instantaneous signalling necessity.
If there is nothing distributed in space, then the objects
won't even know of one another's existence, unless they
are sending signals at all times, which would be problematic.
So you do understand both the need for instantaneous signalling, and
the problem with it.
Post by Alen
If, however, both have 'fields' distributed in flat spacetime,
these fields will interfere with one another as they come into
contact.
This is essentially classic GR. Spacetime is essentially some
component of all the matter and energy in the Universe.
Post by Alen
I don't see why these fields might not together
create the equivalent of a 'surface', of limited extent,
along which the trajectory is a geodesic.
Right.
Post by Alen
As the objects relatively move, they continuously
create the surface within which the relative motion
exists. One could visualise this process in a
stepwise kind of way, if necessary. Whether this is
the best description, or not, I don't see why
interaction of distributed fields with one another
requires signalling between the centres of mass
themselves??
When you have a "distributed field", you have a manifold, and no need
for signalling. That some mathematicians like to divorce the manifold
from the matter / energy that created it, is not *your* problem.

David A. Smith
Alen
2011-01-31 14:27:53 UTC
Permalink
Post by dlzc
...
Post by Alen
I don't understand this instantaneous signalling necessity.
If there is nothing distributed in space, then the objects
won't even know of one another's existence, unless they
are sending signals at all times, which would be problematic.
So you do understand both the need for instantaneous signalling, and
the problem with it.
Post by Alen
If, however, both have 'fields' distributed in flat spacetime,
these fields will interfere with one another as they come into
contact.
This is essentially classic GR.  Spacetime is essentially some
component of all the matter and energy in the Universe.
Post by Alen
I don't see why these fields might not together
create the equivalent of a 'surface', of limited extent,
along which the trajectory is a geodesic.
Right.
Post by Alen
As the objects relatively move, they continuously
create the surface within which the relative motion
exists. One could visualise this process in a
stepwise kind of way, if necessary. Whether this is
the best description, or not, I don't see why
interaction of distributed fields with one another
requires signalling between the centres of mass
themselves??
When you have a "distributed field", you have a manifold, and no need
for signalling.  That some mathematicians like to divorce the manifold
from the matter / energy that created it, is not *your* problem.
David A. Smith
OK - I think we understand each other, lol!!

Alen
Tom Roberts
2011-01-29 00:10:34 UTC
Permalink
Post by Alen
I like
to ask the question: how can one prove that a small
test object is moving along the geodesic of a spacetime
curved by a large object in whose field it is moving?
One models the trajectory of the small object, and computes what measurements of
its position should be as a function of time. Then one compares to such
measurements of the actual object. In the case of Mercury's orbit, the GR
computation is considerably more accurate than previous ones.
Post by Alen
The test object, and the above equation, and the
Schwarzschild equation are local only. They don't prove
the existence of a global field.
Such "proof" is not part of physics.

The THEORY is based on the existence of "global" fields (the adjective is
redundant, as these are all fields on the manifold, and the manifold covers the
universe being modeled).

The Schwarzschild metric covers the world it is modeling; it is not "local only".

Don't be confused by the fact that the line element is expressed in
terms of differentials. The fact that the line element is valid
everywhere and everywhen in the universe being modeled means it
is truly "global".
Post by Alen
Therefore, is there anything that can prove that the local
manifold is not merely something being temporarily created
by the interaction of the test object with the other field,
which doesn't otherwise exist as a manifold?
Such "proof" is not part of physics. It simply is not possible to "prove"
whether a given model is "the way the world actually works", as you seem to think.

The burden is on you to create a model in which "manifolds are being temporarily
created", in order to contrast such a theory with GR, in which the manifold is
eternal and covers the entire universe (i.e. all times and all places).

You'll find that if you try to do so, you'll have to modify the meaning of
"manifold" such that it is completely unrecognizable, and unrelated to the
current meaning.
Post by Alen
Surely we
only infer the existence of a global manifold by observing
localised tests of it!?
The manifold is part of the MODEL, not the world. It has no "existence" at all,
except in the thoughts and minds of people contemplating the theory (which is
not normally considered to be existence).
Post by Alen
Is it not true that we can never have
a global view of a gravitational manifold around a massive
body, and can't prove that it even exists in the absence of
a test object?
Again, such "proofs" are not part of physics.

We can say that GR satisfies a large number of experiments and measurements, and
it has not been definitively refuted; it is the best, generally-accepted model
of gravitation we have today, which implies that its structure, including the
manifold, is a not-unreasonable way to think about the world. Until a better
theory comes along....


Tom Roberts
Alen
2011-01-29 03:44:25 UTC
Permalink
Post by Tom Roberts
Post by Alen
I like
to ask the question: how can one prove that a small
test object is moving along the geodesic of a spacetime
curved by a large object in whose field it is moving?
One models the trajectory of the small object, and computes what measurements of
its position should be as a function of time. Then one compares to such
measurements of the actual object. In the case of Mercury's orbit, the GR
computation is considerably more accurate than previous ones.
It is more accurate, yes. That is why, I think, that people have
been trying to create the Schwarzschild equation when
investigating alternative gravitational models.
Post by Tom Roberts
Post by Alen
The test object, and the above equation, and the
Schwarzschild equation are local only. They don't prove
the existence of a global field.
Such "proof" is not part of physics.
The THEORY is based on the existence of "global" fields (the adjective is
redundant, as these are all fields on the manifold, and the manifold covers the
universe being modeled).
The Schwarzschild metric covers the world it is modeling; it is not "local only".
        Don't be confused by the fact that the line element is expressed in
        terms of differentials. The fact that the line element is valid
        everywhere and everywhen in the universe being modeled means it
        is truly "global".
Post by Alen
Therefore, is there anything that can prove that the local
manifold is not merely something being temporarily created
by the interaction of the test object with the other field,
which doesn't otherwise exist as a manifold?
Such "proof" is not part of physics. It simply is not possible to "prove"
whether a given model is "the way the world actually works", as you seem to think.
The burden is on you to create a model in which "manifolds are being temporarily
created", in order to contrast such a theory with GR, in which the manifold is
eternal and covers the entire universe (i.e. all times and all places).
You'll find that if you try to do so, you'll have to modify the meaning of
"manifold" such that it is completely unrecognizable, and unrelated to the
current meaning.
I think that it is a very important question, whether it can
be currently answered or not. If the global manifold is
everywhere in spacetime, independently of the presence of
any test object, then I think we can forget about any notion
of a 'force field' picture of gravitation, or the presence of any
other manifold, since the global manifold is sufficient of itself
to account for the whole gravitational phenomenon.

If, however, the manifold is being temporarily created by the
gravitational interaction with a test object (let us say that the
fields of the massive body and the test object deform one
another and jointly create a temporary 'surface', in which the
trajectory is a geodesic), then the existence of a force-field
picture becomes possible, or necessary, and, also,
one would suppose that, in the absence of a test object,
the massive body, and its field, would exist in a flat spacetime.
So, in that case, we also have the presence of a euclidian
manifold.

So I think it is a very important question to consider,
because of the radical difference it produces in the
resulting theory.
Post by Tom Roberts
Post by Alen
Surely we
only infer the existence of a global manifold by observing
localised tests of it!?
The manifold is part of the MODEL, not the world. It has no "existence" at all,
except in the thoughts and minds of people contemplating the theory (which is
not normally considered to be existence).
Post by Alen
Is it not true that we can never have
a global view of a gravitational manifold around a massive
body, and can't prove that it even exists in the absence of
a test object?
Again, such "proofs" are not part of physics.
We can say that GR satisfies a large number of experiments and measurements, and
it has not been definitively refuted; it is the best, generally-accepted model
of gravitation we have today, which implies that its structure, including the
manifold, is a not-unreasonable way to think about the world. Until a better
theory comes along....
Tom Roberts
OK - but let that not stop us investigating
and working on alternatives, I say :) :)

Alen
Tom Roberts
2011-01-29 18:31:49 UTC
Permalink
Post by Alen
If the global manifold is
everywhere in spacetime, independently of the presence of
any test object, then I think we can forget about any notion
of a 'force field' picture of gravitation,
Not true. EVERY currently accepted theory of physics is based on a manifold,
which models either space or space-time. This includes all models in which
gravity is a force (e.g. Newtonian mechanics, the various field theories of
gravity, etc.). It also includes GR, in which gravity is not a force.

A field is necessarily a field on a manifold -- that's what the
word means (in this context).
Post by Alen
If, however, the manifold is being temporarily created by the
gravitational interaction [...]
You need to learn what a manifold actually is. You use the word in wildly
incorrect ways. This will require more precise thinking on your part, and a
STUDY of the literature to learn how the nomenclature is actually used.

You also need to recognize the difference between world and model. Manifolds and
fields are parts of the MODEL, not the world.


Tom Roberts
Alen
2011-01-30 02:47:04 UTC
Permalink
Post by Tom Roberts
Post by Alen
If the global manifold is
everywhere in spacetime, independently of the presence of
any test object, then I think we can forget about any notion
of a 'force field' picture of gravitation,
Not true. EVERY currently accepted theory of physics is based on a manifold,
which models either space or space-time. This includes all models in which
gravity is a force (e.g. Newtonian mechanics, the various field theories of
gravity, etc.). It also includes GR, in which gravity is not a force.
        A field is necessarily a field on a manifold -- that's what the
        word means (in this context).
Post by Alen
If, however, the manifold is being temporarily created by the
gravitational interaction [...]
You need to learn what a manifold actually is. You use the word in wildly
incorrect ways. This will require more precise thinking on your part, and a
STUDY of the literature to learn how the nomenclature is actually used.
You also need to recognize the difference between world and model. Manifolds and
fields are parts of the MODEL, not the world.
Tom Roberts
I understand what you are saying and, yes,
I do not try to achieve technical perfection all
the time. I just expect people will understand what
I am saying - e.g. that there is a distinction in type
between a force field and a geometrical explanation
for gravitation, even if some kind of manifold is
involved in both cases. I know that one distinguishes
the 'metric' from the 'manifold', with the metric as
a kind of mathematical structure on the manifold.
But these fine distinctions seem to easily cause people
confusion as much as they do illumination. You can
find forums where people are arguing about how
a 'metric' relates to a 'manifold' etc.

I know that there is a distinction between model
and the actual world, but I see the ideal as being where
the model accurately represents the world, rather than
just being a basis for computing predictions. In that
respect I don't mind failing to refer to the distinction, even
if I know it exists, unless it is really necessary. For me,
the ideal is to try to have models that would be workable
as physical realities, just like, for example, a workshop
manual accurately describes the physical engine. Then
one does not mind referring to an illustration in the
manual as 'the engine', even though it is only a
partial representation of the engine etc.

The fact that I skip over fine distinctions doesn't
necessarily mean that I am not aware they exist.

Alen
Tim Golden BandTech.com
2011-01-31 16:55:16 UTC
Permalink
Post by Alen
Post by Tom Roberts
Post by Alen
If the global manifold is
everywhere in spacetime, independently of the presence of
any test object, then I think we can forget about any notion
of a 'force field' picture of gravitation,
Not true. EVERY currently accepted theory of physics is based on a manifold,
which models either space or space-time. This includes all models in which
gravity is a force (e.g. Newtonian mechanics, the various field theories of
gravity, etc.). It also includes GR, in which gravity is not a force.
        A field is necessarily a field on a manifold -- that's what the
        word means (in this context).
Post by Alen
If, however, the manifold is being temporarily created by the
gravitational interaction [...]
You need to learn what a manifold actually is. You use the word in wildly
incorrect ways. This will require more precise thinking on your part, and a
STUDY of the literature to learn how the nomenclature is actually used.
You also need to recognize the difference between world and model. Manifolds and
fields are parts of the MODEL, not the world.
Tom Roberts
I understand what you are saying and, yes,
I do not try to achieve technical perfection all
the time. I just expect people will understand what
I am saying - e.g. that there is a distinction in type
between a force field and a geometrical explanation
for gravitation, even if some kind of manifold is
involved in both cases. I know that one distinguishes
the 'metric' from the 'manifold', with the metric as
a kind of mathematical structure on the manifold.
But these fine distinctions seem to easily cause people
confusion as much as they do illumination. You can
find forums where people are arguing about how
a 'metric' relates to a 'manifold' etc.
I know that there is a distinction between model
and the actual world, but I see the ideal as being where
the model accurately represents the world, rather than
just being a basis for computing predictions. In that
respect I don't mind failing to refer to the distinction, even
if I know it exists, unless it is really necessary. For me,
the ideal is to try to have models that would be workable
as physical realities, just like, for example, a workshop
manual accurately describes the physical engine. Then
one does not mind referring to an illustration in the
manual as 'the engine', even though it is only a
partial representation of the engine etc.
I think your statement here is very clean Alen.
The one thing that we can probably all agree on is that the technical
writer of the manual matters quite a lot. When the manual is simply
written and accurately portrays the engine then we have a high quality
manual.

In this area of physics we know that AE is a purist of the form that
would write an excellent engine manual. Could it be then that the
tools available at the time of his writing were not actually
sufficient to get his points across? Yes, this is a possibility. We
may eventually be able to understand the engine better, and it will
likely require a new manual.

I am not able to sense the metric versus manifold distinction that you
make, though I am into structured spacetime, which makes its own
distinctions that likewise challenge existing thought constructs. From
my perspective the construction of an assymetrical metric on a tensor
that supposedly upholds isotropic principles is a conflicted
construction. This is the Minkowski metric that I am attacking. Time
cannot stand with space so symmetrically, and this piece does involve
empirical information, for we witness a unidirectional quality in time
and a lack of dimensional freedom; the very same freedom which allows
us to state the three dimensional quality of space.

This consideration does not deny unified spacetime, for if we allow a
structured representation such as the product space
P1 P2 P3
which is nearly
t x z
where t is unidirectional time, x a one dimensional component, and z a
two dimensional complex component, then we arrive informationally near
to the antisymmetric tensor with its redundancy removed, and we see a
rotational quality within this structure that likewise can portray
electromagnetic structure within spacetime itself, which is just where
is belongs, especially down at the particle level.

This unidirectional time that I speak of will not be had in modern
mathematics, where the real value is considered fundamental. Instead,
by generalizing sign we can arrive in a system where magnitude
(distance) is fundamental, and the real value lays as a two-signed
form constructed out of magnitude; the unidirectional (time) form
being the one-signed numbers, which precede the two-signed numbers in
the progression
P1 P2 P3 ...
and the P3 (three-signed numbers) naturally occuring out of the same
rule set, these happening to be completely consistent with the
existing complex numbers, though constructed out of this principle of
generalized sign. It also happens that there is a behavioral
breakpoint in distance behavior within the progression after P3, where
the familiar
|AB| = |A||B|
no longer holds, and the effects of dimensional collapse are evident,
which I do hope Steve is aware of. Polysign promises to deliver
emergent spacetime out of pregeometry, which in this case is pure
algebra. Nicely enough the system's geometry is simplex based, and yet
the Fullerites don't give a damn. They could have emergent spacetime,
but they don't want it, and with unidirectional time. The physical
theory which comes out of polysign will support spacetime even if the
dimensional progression continues.

The marriage of continuous and discrete; this is somewhat the
awareness that runs through much of physics. The multidimensional
value is a discrete/continuous concept that does have a rewrite
waiting in the wings. The simple statement on isotropic space that I
made earlier is the easiest way in to challenging relativity; at least
from my perpective it is. Spacetime is not isotropic. Spacetime is
structured.

The proof of this is simpler than you will believe; look right and I
see a tree; look left and I see a bowl; therefore spacetime is not
isotropic. Now you will insist on inserting some conditionals and I
would be happy to take this argument up if you'd like as an exercise
for both of us. Because GR does build off of SR then this may become a
more fundamental falsification of the construction since the tensor
usage is flawed.

- Tim
Post by Alen
The fact that I skip over fine distinctions doesn't
necessarily mean that I am not aware they exist.
Alen
shuba
2011-02-01 00:26:28 UTC
Permalink
From my perspective the construction of an assymetrical metric on a
tensor that supposedly upholds isotropic principles is a conflicted
construction.
It's always fun to see how cranks justify their rejection of relativity.
This is the Minkowski metric that I am attacking.
If you say so. By your description, what you are attacking isn't any
concept used in relativity. Even if you meant to write "manifold" instead
of the nonsensical "tensor" in your sentence, it's still wrong, as the
metric is taken to be symmetric. Presumably you don't know what it means
for a metric to be symmetric, and are making up a personal definition
based on ignorance or misunderstanding. Plus, you appear equally clueless
about the meaning of isotropy, as well as curvature. Keep going, though,
it's very entertaining.


---Tim Shuba---
Tim Golden BandTech.com
2011-02-01 14:57:55 UTC
Permalink
Post by shuba
From my perspective the construction of an assymetrical metric on a
tensor that supposedly upholds isotropic principles is a conflicted
construction.
It's always fun to see how cranks justify their rejection of relativity.
This is the Minkowski metric that I am attacking.
If you say so. By your description, what you are attacking isn't any
concept used in relativity. Even if you meant to write "manifold" instead
of the nonsensical "tensor" in your sentence, it's still wrong, as the
metric is taken to be symmetric. Presumably you don't know what it means
for a metric to be symmetric, and are making up a personal definition
based on ignorance or misunderstanding. Plus, you appear equally clueless
about the meaning of isotropy, as well as curvature. Keep going, though,
it's very entertaining.
         ---Tim Shuba---
Well shuba I am willing to argue isotropy with you.
"Electromagnetics: An isotropic medium is one such that the
permittivity, ε, and permeability, μ, of the medium are uniform in all
directions of the medium, the most simple instance being free space."
- http://en.wikipedia.org/wiki/Isotropy#Physics
This is a fine instance that exposes the nuance that allows me to
attack isotropy: if space were completely free of matter then the
space would be isotropic, but since space is not free of matter then
it is not isotropic, so long as that material is varied in its
qualities, which it is.

That space lacks qualities without any material in it: this seems to
be the hinge that the belief in isotropy hinges upon. It is like a
simplified physics problem in which there are perhaps two objects
which interact in the universe. Remove these two, and yes, you will
have an isotropic medium. This is however not reality. Space is real.
Matter in space is real, and this is the where I attack isotropy.

- Tim
shuba
2011-02-01 20:34:05 UTC
Permalink
Post by Tim Golden BandTech.com
This is a fine instance that exposes the nuance that allows me to
attack isotropy: if space were completely free of matter then the
space would be isotropic, but since space is not free of matter then
it is not isotropic, so long as that material is varied in its
qualities, which it is.
I hope you are able to keep this profound secret away for cosmology
researchers. They will be devastated to learn that the universe contains
matter and energy, not all of which is distributed perfectly
homogeneously throughout all directions of space.
Post by Tim Golden BandTech.com
That space lacks qualities without any material in it: this seems to
be the hinge that the belief in isotropy hinges upon. It is like a
simplified physics problem in which there are perhaps two objects
which interact in the universe. Remove these two, and yes, you will
have an isotropic medium. This is however not reality. Space is real.
Matter in space is real, and this is the where I attack isotropy.
No one knowledgeable thinks that flat spacetime precisely models the real
world. Special relativity has a domain of applicability which is subsumed
by general relativity. You may as well attack Newtonian physics on the
basis that its first law is "unreal", given that no object can be
force-free.

Fundamental physics, and in fact all modern science, has always
progressed by breaking up the study of nature into necessarily incomplete
subdivisions where effects produced by the rest of the universe are
either ignored or approximated. If you are going to prattle on about
which scientific concepts do or do not correspond to reality, you may as
well take up theology. Your so-called attacks are nothing but tilting at
windmills.


---Tim Shuba---
Tim Golden BandTech.com
2011-02-01 23:50:13 UTC
Permalink
Post by shuba
Post by Tim Golden BandTech.com
This is a fine instance that exposes the nuance that allows me to
attack isotropy: if space were completely free of matter then the
space would be isotropic, but since space is not free of matter then
it is not isotropic, so long as that material is varied in its
qualities, which it is.
I hope you are able to keep this profound secret away for cosmology
researchers. They will be devastated to learn that the universe contains
matter and energy, not all of which is distributed perfectly
homogeneously throughout all directions of space.
Post by Tim Golden BandTech.com
That space lacks qualities without any material in it: this seems to
be the hinge that the belief in isotropy hinges upon. It is like a
simplified physics problem in which there are perhaps two objects
which interact in the universe. Remove these two, and yes, you will
have an isotropic medium. This is however not reality. Space is real.
Matter in space is real, and this is the where I attack isotropy.
No one knowledgeable thinks that flat spacetime precisely models the real
world. Special relativity has a domain of applicability which is subsumed
by general relativity. You may as well attack Newtonian physics on the
basis that its first law is "unreal", given that no object can be
force-free.
Fundamental physics, and in fact all modern science, has always
progressed by breaking up the study of nature into necessarily incomplete
subdivisions where effects produced by the rest of the universe are
either ignored or approximated. If you are going to prattle on about
which scientific concepts do or do not correspond to reality, you may as
well take up theology. Your so-called attacks are nothing but tilting at
windmills.
         ---Tim Shuba---
The content is really lacking in your post, but I will carry on with
you because you do seem to be a strong minded person, and your insults
are fairly well founded.

There are many more aspects by which to challenge the isotropic
assumption. One of these is the fact that electromagnetic phenomena
are properties of spacetime itself. The propagation constants c,
epsilon naught, and mu naught, are all attributed to spacetime itself.
Here again we see structured concepts from an entity that is claimed
to be homogeneous. Let's not forget that electromagnetic behaviors
come with quite some geometrical relations, including rotational
phenomena such as the cross product portrays. The cross product in not
a general dimensional phenomenon, so that its naturalness can be
challenged, and what this challenge leads to is a realization that
spacetime is structured.

The fact that time has unidirectional behavior disallows a symmetrical
treatment as the tensor portrays, where time and space are mixed into
the same supposedly isotropic structure. Well, the Minkowski metric,
or whatever other asymmetrical metric that you impose to remedy the
problem introduces structure into spacetime. Now, shuba, since you are
carrying on here could you please answer the following two questions:
1. Is space isotropic?
2. Is spacetime isotropic?
I do not honestly know what your answer to number two will be. I
suspect that the answer does vary even within the social circles that
manage to maintain a more mainstream position than I do. Lastly, I did
give a solid example to which you have not provided any content, and
this is a weak mark on your own side of this argument. To state that
you believe that space is isotropic because others believe that it is
isotropic is a highly unscientific approach. This is the state of
mimicry, and in your response I see many key phrases that imply that
this is the basis by which you wish to argue, and it is no basis at
all. Physical correspondence is something that the human does struggle
with, but if you are going to bother attempting an argument here, then
let's hear it, for thus far your content is nearly nill.

The simplest definition of isotropic is
"the same in all directions"
but all that I need to do is look right, then look left, and I see
that the space that I am in is not the same in all directions. From
this perspective you could provide a nuanced argument if you like, but
it the nuance is to average out everything to force the space into an
isotropic quality then your own side will be standing on a crutch that
I will easily knock away, for under this condition there never will be
such a thing as an anisotropic space, and perhaps it is by
investigating the anisotropic space that we might come a little
further. For instance if we were to impose a magnetic dipole through
the center of a sphere, would this do? Do we know any objects like
this?

I do have much more to say on this topic, and will say. The awareness
that at the particulate level Maxwell's equations have failed does not
seem to be in the mainstream awareness. That we are conglomerate
beings may answer why humans believe that space is isotropic; that
averaging out thing that I attacked a little while ago is largely
operant for a large group of particles, whose spin characteristics are
essentially hidden to us, only to be discovered late in the scientific
development, where a raw charge was presumed to be a particle, which
is a fairly isotropic concept. In some ways it is the ultimate
Maxwellian statement that the raw charge does not exist devoid of a
magnetic moment. The culmination of this realization will be when the
behavior is brought to spacetime itself, which is to say that the spin
structure will eventually be regarded as a spacetime characteristic.
From this structured perspective I believe that the relative reference
frame will then be invoked, and this will round out the perspective
and get us back to the ordinary semblance. That relative reference
frames can be invoked on structured (not isotropic) systems is yet to
be done properly. I can do a little bit of it, but I don't have any
finality in my attempts yet. You are welcome to consider these details
and criticize them, please, but please do it with some content.

Oh, and what's wrong with windmills?

- Tim
shuba
2011-02-02 17:27:57 UTC
Permalink
Post by Tim Golden BandTech.com
Let's not forget that electromagnetic behaviors
come with quite some geometrical relations, including rotational
phenomena such as the cross product portrays. The cross product in not
a general dimensional phenomenon
So use an antisymmetric tensor, which can be defined in any dimension.
That is how Maxwell's equations are written in covariant form.
Post by Tim Golden BandTech.com
1. Is space isotropic?
2. Is spacetime isotropic?
Space is isotropic for both Newtonian physics and special relativity.
Experimentally, it's true to within some rather tight error bars, both
locally and at cosmological scales.
http://prl.aps.org/abstract/PRL/v57/i25/p3125_1
http://prl.aps.org/abstract/PRL/v54/i22/p2387_1
http://prl.aps.org/abstract/PRL/v42/i9/p549_1
http://prl.aps.org/abstract/PRL/v90/i20/e201101

It doesn't make sense to attempt to apply the concept of isotropy to
spacetime without having a good definition of what that means. I don't
have one. I've read about a definition based on Killing vector fields,
but I think this applies to specific manifolds, not to spacetime in
general.
Post by Tim Golden BandTech.com
The simplest definition of isotropic is
"the same in all directions"
but all that I need to do is look right, then look left, and I see
that the space that I am in is not the same in all directions.
You can see space? Fascinating. Do you also hear, smell, and feel it?
Post by Tim Golden BandTech.com
You are welcome to consider these details
and criticize them, please, but please do it with some content.
No thanks. Try the Natural Philosophy Alliance. They may have exactly
what you want.


---Tim Shuba---
Tom Roberts
2011-02-02 21:54:25 UTC
Permalink
Post by shuba
It doesn't make sense to attempt to apply the concept of isotropy to
spacetime without having a good definition of what that means. I don't
have one. I've read about a definition based on Killing vector fields,
but I think this applies to specific manifolds, not to spacetime in
general.
Spacetime is clearly not isotropic -- time is quite different from space.

The usual meaning of isotropy is that the manifold and its metric are the same
in all directions from a given point; this is equivalent to the technical
definition: the existence of a set of Killing vector fields conforming to the
rotation group SO(N). In relativity, the symmetry group is SO(1,N-1), not SO(N),
and spacetime is not isotropic.

N is the dimension of the manifold.

If the manifold is isotropic everywhere, that is equivalent to its being
homogeneous, and that implies the existence of an additional N Killing vectors
corresponding to translations.

Minkowski spacetime has ten Killing vectors: 6 from SO(1,3)
(three rotations, three boosts), and 4 translations. Ten is the
maximum number of independent Killing vectors for a 4-D manifold.


Tom Roberts
BURT
2011-02-03 04:12:13 UTC
Permalink
Post by Tom Roberts
Post by shuba
It doesn't make sense to attempt to apply the concept of isotropy to
spacetime without having a good definition of what that means. I don't
have one. I've read about a definition based on Killing vector fields,
but I think this applies to specific manifolds, not to spacetime in
general.
Spacetime is clearly not isotropic -- time is quite different from space.
The usual meaning of isotropy is that the manifold and its metric are the same
in all directions from a given point; this is equivalent to the technical
definition: the existence of a set of Killing vector fields conforming to the
rotation group SO(N). In relativity, the symmetry group is SO(1,N-1), not SO(N),
and spacetime is not isotropic.
        N is the dimension of the manifold.
If the manifold is isotropic everywhere, that is equivalent to its being
homogeneous, and that implies the existence of an additional N Killing vectors
corresponding to translations.
        Minkowski spacetime has ten Killing vectors: 6 from SO(1,3)
        (three rotations, three boosts), and 4 translations. Ten is the
        maximum number of independent Killing vectors for a 4-D manifold.
Tom Roberts
All theories are incomplete; including curved space.

Mitch Raemsch
shuba
2011-02-04 17:57:01 UTC
Permalink
Post by Tom Roberts
Spacetime is clearly not isotropic -- time is quite different from space.
Certainly time and space are different, I've never doubted that! On its
face, the idea of spacetime being "the same" in all directions reads as a
non sequitur, and that's why I said I don't have a definition myself
which applies. It's just that I can imagine definitions (perhaps
nonstandard) where the term "isotropy" could reasonably apply to
spacetime. As an example, there are so-called isotropic coordinates;
Chris Hillman gave a nifty usenet persentation of how they work for the
exterior Schwarzschild geometry.

http://groups.google.com/group/sci.astro/msg/5bd8cc90d6e6833c

It seems reasonable to use the term "isotropic spacetime" to refer to
geometries on which such coordinates can be defined. By searching the
web, the term is used, but almost always refers to spatial hyperslices.

Thanks for the brief description of the Killing vectors. I know it's an
important concept for understanding symmetries of a manifold with a
metric, and I intend to learn more about it.


---Tim Shuba---
Daryl McCullough
2011-02-05 00:18:01 UTC
Permalink
shuba says...
Post by shuba
Post by Tom Roberts
Spacetime is clearly not isotropic -- time is quite different from space.
Certainly time and space are different, I've never doubted that! On its
face, the idea of spacetime being "the same" in all directions reads as a
non sequitur, and that's why I said I don't have a definition myself
which applies. It's just that I can imagine definitions (perhaps
nonstandard) where the term "isotropy" could reasonably apply to
spacetime. As an example, there are so-called isotropic coordinates;
Chris Hillman gave a nifty usenet persentation of how they work for the
exterior Schwarzschild geometry.
http://groups.google.com/group/sci.astro/msg/5bd8cc90d6e6833c
It seems reasonable to use the term "isotropic spacetime" to refer to
geometries on which such coordinates can be defined. By searching the
web, the term is used, but almost always refers to spatial hyperslices.
Right, I think that people normally only use the word "isotropic" to
refer to spatial hyperslices. You could certainly talk about isotropy
for the full 4-dimensional spacetime, but spacetime is *never* isotropic
in that sense.

--
Daryl McCullough
Ithaca, NY
BURT
2011-02-05 01:24:29 UTC
Permalink
Post by Daryl McCullough
shuba says...
Post by shuba
Post by Tom Roberts
Spacetime is clearly not isotropic -- time is quite different from space.
Certainly time and space are different, I've never doubted that! On its
face, the idea of spacetime being "the same" in all directions reads as a
non sequitur, and that's why I said I don't have a definition myself
which applies. It's just that I can imagine definitions (perhaps
nonstandard) where the term "isotropy" could reasonably apply to
spacetime. As an example, there are so-called isotropic coordinates;
Chris Hillman gave a nifty usenet persentation of how they work for the
exterior Schwarzschild geometry.
http://groups.google.com/group/sci.astro/msg/5bd8cc90d6e6833c
It seems reasonable to use the term "isotropic spacetime" to refer to
geometries on which such coordinates can be defined. By searching the
web, the term is used, but almost always refers to spatial hyperslices.
Right, I think that people normally only use the word "isotropic" to
refer to spatial hyperslices. You could certainly talk about isotropy
for the full 4-dimensional spacetime, but spacetime is *never* isotropic
in that sense.
--
Daryl McCullough
Ithaca, NY- Hide quoted text -
- Show quoted text -
There is One higher dimension and it is spatial but time occupies it.
You can never destroy the togetherness of time and space.
A single point in Einstein's continuum contains both space and time
aether.

Mitch Raemsch
Tim Golden BandTech.com
2011-02-03 14:54:50 UTC
Permalink
Post by shuba
Post by Tim Golden BandTech.com
Let's not forget that electromagnetic behaviors
come with quite some geometrical relations, including rotational
phenomena such as the cross product portrays. The cross product in not
a general dimensional phenomenon
So use an antisymmetric tensor, which can be defined in any dimension.
That is how Maxwell's equations are written in covariant form.
Post by Tim Golden BandTech.com
   1. Is space isotropic?
   2. Is spacetime isotropic?
Space is isotropic for both Newtonian physics and special relativity.
Experimentally, it's true to within some rather tight error bars, both
locally and at cosmological scales.
   http://prl.aps.org/abstract/PRL/v57/i25/p3125_1
   http://prl.aps.org/abstract/PRL/v54/i22/p2387_1
   http://prl.aps.org/abstract/PRL/v42/i9/p549_1
   http://prl.aps.org/abstract/PRL/v90/i20/e201101
Access to these articles requires a membership. I cannot access these
docs.
Post by shuba
It doesn't make sense to attempt to apply the concept of isotropy to
spacetime without having a good definition of what that means. I don't
have one. I've read about a definition based on Killing vector fields,
but I think this applies to specific manifolds, not to spacetime in
general.
Well... Here we have your first content. And it does seem quite
interesting that the tensor form of three dimensional space is
inherently isotropic, but that you concede that the 4D form is not,
even while it still gets squeezed into a tensor, which is supposed to
be rotationally invariant, or more generally consists of an arbitrary
basis. From my perspective you have just invalidated the 4D tensor
usage of relativity theory.
Post by shuba
Post by Tim Golden BandTech.com
The simplest definition of isotropic is
   "the same in all directions"
but all that I need to do is look right, then look left, and I see
that the space that I am in is not the same in all directions.
You can see space? Fascinating. Do you also hear, smell, and feel it?
Well, here you are again treating space as if it does not contain any
objects. This is indeed an isotropic stance, but upon admitting that
real space, like the stuff that you wave your hand through, does have
objects in it, and especially under GR where this space takes on
curvature, then it is clear that the word isotropic does deserve
further scrutiny.
Post by shuba
Post by Tim Golden BandTech.com
You are welcome to consider these details
and criticize them, please, but please do it with some content.
No thanks. Try the Natural Philosophy Alliance. They may have exactly
what you want.
         ---Tim Shuba---
I find it interesting that you never addressed some of my questions.
Particularly if we were to observe a sphere with a magnetic dipole
running through its center would this be consistent with an isotropic
space? Here you see is a real situation; the planet Earth. But the
structural qualities do not end there. Reality is highly structured.
Its stability is quite impressive on our own time scale, and if we
have mistaken such fundamental qualities then there is hope of our
understanding entering a greater stage of developmnet. Still, I do
believe it is wise to consider the human position as acting in
hindsight, and lacking access to the basis, for we are products of the
basis. This explains how it is that we grapple with the qualities of
reality; we are its prisoners.

We are prisoners of spacetime.

- Tim
Daryl McCullough
2011-02-03 16:46:28 UTC
Permalink
Tim Golden BandTech.com says...
Post by Tim Golden BandTech.com
Well... Here we have your first content. And it does seem quite
interesting that the tensor form of three dimensional space is
inherently isotropic, but that you concede that the 4D form is not,
even while it still gets squeezed into a tensor, which is supposed to
be rotationally invariant,
Being a tensor doesn't mean that it is rotationally invariant.
The metric tensor of Minkowsky spacetime is invariant under
combinations of the following operations:

1. Translations (change of location and/or time)
2. Spatial rotations (change of orientation)
3. Lorentz boosts (change of reference frame)
Post by Tim Golden BandTech.com
or more generally consists of an arbitrary
basis. From my perspective you have just invalidated the 4D tensor
usage of relativity theory.
I don't think you know what you are talking about. The use
of 4-dimensional tensors doesn't imply invariance under 4-dimensional
rotations.

Tensors, vectors, etc. can be used whenever there is an N-dimensional
manifold with a notion of smooth functions on the manifold (smooth
meaning continuous and having derivatives). 4D tensors can be used
with Newtonian physics, just as well as with Special and General
Relativity. They can be used in thermodynamics, where the dimensions
are Volume, Pressure, Temperature.

I think you are getting two different concepts confused:
(1) The covariance of the components of a tensor under changes
of coordinates, and (2) The invariance of a tensor field under
symmetry operations on the manifold. All tensors satisfy (1).
But only in certain special cases do the tensors satisfy (2).

The distinction is sometimes called "passive" versus "active"
coordinate transformations, but the latter is not really
a coordinate transformation, it is a mapping from the manifold
to itself that can be *described* using coordinates.

--
Daryl McCullough
Ithaca, NY
Tim Golden BandTech.com
2011-02-03 22:31:45 UTC
Permalink
Post by Daryl McCullough
Tim Golden BandTech.com says...
Post by Tim Golden BandTech.com
Well... Here we have your first content. And it does seem quite
interesting that the tensor form of three dimensional space is
inherently isotropic, but that you concede that the 4D form is not,
even while it still gets squeezed into a tensor, which is supposed to
be rotationally invariant,
Being a tensor doesn't mean that it is rotationally invariant.
The metric tensor of Minkowsky spacetime is invariant under
1. Translations (change of location and/or time)
2. Spatial rotations (change of orientation)
3. Lorentz boosts (change of reference frame)
Post by Tim Golden BandTech.com
or more generally consists of an arbitrary
basis. From my perspective you have just invalidated the 4D tensor
usage of relativity theory.
I don't think you know what you are talking about. The use
of 4-dimensional tensors doesn't imply invariance under 4-dimensional
rotations.
Originally, yes, it did. I admit that relativity theory does not use
it this way and so the relativistic usage is only a pseudotensor.
Still, the issue of relative reference frames, isotropic space
interpretation, and tensor basics are all connected. When the tensor
was used in 3D flat space then the arbitrary reference frame made more
sense. Because time is unidirectional there is clearly an ambiguity in
choosing an arbitrary reference frame, and this conflict was somehow
washed clean. The tensor with arbitrary basis is about as close as you
can get to the isotropic claim. How rarely we consider this
representation to include all objects in spacetime... how can it? It
is merely a 4x4 series of floats. Well, so we use functions to
represent all material. A density function... now that's going to come
out clean, eh? Sorry, but I don't think we're anywhere near done yet.
Post by Daryl McCullough
Tensors, vectors, etc. can be used whenever there is an N-dimensional
manifold with a notion of smooth functions on the manifold (smooth
meaning continuous and having derivatives). 4D tensors can be used
with Newtonian physics, just as well as with Special and General
Relativity. They can be used in thermodynamics, where the dimensions
are Volume, Pressure, Temperature.
(1) The covariance of the components of a tensor under changes
of coordinates, and (2) The invariance of a tensor field under
symmetry operations on the manifold. All tensors satisfy (1).
But only in certain special cases do the tensors satisfy (2).
The distinction is sometimes called "passive" versus "active"
coordinate transformations, but the latter is not really
a coordinate transformation, it is a mapping from the manifold
to itself that can be *described* using coordinates.
This is new to me. I'll try to keep an open mind on this.
This is not the tensor that I have studied, where the arbitrary basis
is fundamental.
This was the point of the representation; the actual basis becomes
generalized and expressions can be constructed without regard for say
x,y,z type of coordinates, especially when the equations are all going
to be the same. These become x0,x1,x2 and the indexing becomes
implied. Now, when we chuck t in there then yes, the symmetry is
broken, and this method deserves this criticism. Thanks Daryl for your
detailed response. I'll try to keep my eye out for more from your
perspective.

- Tim
Post by Daryl McCullough
--
Daryl McCullough
Ithaca, NY
BURT
2011-02-03 22:42:36 UTC
Permalink
Post by Tim Golden BandTech.com
Post by Daryl McCullough
Tim Golden BandTech.com says...
Post by Tim Golden BandTech.com
Well... Here we have your first content. And it does seem quite
interesting that the tensor form of three dimensional space is
inherently isotropic, but that you concede that the 4D form is not,
even while it still gets squeezed into a tensor, which is supposed to
be rotationally invariant,
Being a tensor doesn't mean that it is rotationally invariant.
The metric tensor of Minkowsky spacetime is invariant under
1. Translations (change of location and/or time)
2. Spatial rotations (change of orientation)
3. Lorentz boosts (change of reference frame)
Post by Tim Golden BandTech.com
or more generally consists of an arbitrary
basis. From my perspective you have just invalidated the 4D tensor
usage of relativity theory.
I don't think you know what you are talking about. The use
of 4-dimensional tensors doesn't imply invariance under 4-dimensional
rotations.
Originally, yes, it did. I admit that relativity theory does not use
it this way and so the relativistic usage is only a pseudotensor.
Still, the issue of relative reference frames, isotropic space
interpretation, and tensor basics are all connected. When the tensor
was used in 3D flat space then the arbitrary reference frame made more
sense. Because time is unidirectional there is clearly an ambiguity in
choosing an arbitrary reference frame, and this conflict was somehow
washed clean. The tensor with arbitrary basis is about as close as you
can get to the isotropic claim. How rarely we consider this
representation to include all objects in spacetime... how can it? It
is merely a 4x4 series of floats. Well, so we use functions to
represent all material. A density function... now that's going to come
out clean, eh? Sorry, but I don't think we're anywhere near done yet.
Post by Daryl McCullough
Tensors, vectors, etc. can be used whenever there is an N-dimensional
manifold with a notion of smooth functions on the manifold (smooth
meaning continuous and having derivatives). 4D tensors can be used
with Newtonian physics, just as well as with Special and General
Relativity. They can be used in thermodynamics, where the dimensions
are Volume, Pressure, Temperature.
(1) The covariance of the components of a tensor under changes
of coordinates, and (2) The invariance of a tensor field under
symmetry operations on the manifold. All tensors satisfy (1).
But only in certain special cases do the tensors satisfy (2).
The distinction is sometimes called "passive" versus "active"
coordinate transformations, but the latter is not really
a coordinate transformation, it is a mapping from the manifold
to itself that can be *described* using coordinates.
This is new to me. I'll try to keep an open mind on this.
This is not the tensor that I have studied, where the arbitrary basis
is fundamental.
This was the point of the representation; the actual basis becomes
generalized and expressions can be constructed without regard for say
x,y,z type of coordinates, especially when the equations are all going
to be the same. These become x0,x1,x2 and the indexing becomes
implied. Now, when we chuck t in there then yes, the symmetry is
broken, and this method deserves this criticism. Thanks Daryl for your
detailed response. I'll try to keep my eye out for more from your
perspective.
 - Tim
Post by Daryl McCullough
--
Daryl McCullough
Ithaca, NY- Hide quoted text -
- Show quoted text -- Hide quoted text -
- Show quoted text -- Hide quoted text -
- Show quoted text -
Gravity is the point of round curve creation around mass.
God is creating gravity field around mass.

Mitch Raemsch
Daryl McCullough
2011-02-03 23:54:31 UTC
Permalink
Tim Golden BandTech.com says...
Post by Tim Golden BandTech.com
Post by Daryl McCullough
I don't think you know what you are talking about. The use
of 4-dimensional tensors doesn't imply invariance under 4-dimensional
rotations.
Originally, yes, it did.
No, it didn't. One of the uses of tensors is explicitly for describing
anisotropic media (for example, look at the section called
"Anisotropic Materials" on this page:
http://en.wikipedia.org/wiki/Hooke%27s_law
Post by Tim Golden BandTech.com
I admit that relativity theory does not use it this way and so
the relativistic usage is only a pseudotensor.
I think you are confused. The metric tensor is a tensor, not
a pseudotensor.

Often, pseudotensors arise in *nonrelativistic* physics, but they
become full-fledged tensors in relativistic physics. For example,
the magnetic field B is not a tensor, but the full electromagnetic
tensor F^ij is. For another example, angular momentum is not a tensor,
but the relativistic generalization *is*.
Post by Tim Golden BandTech.com
Still, the issue of relative reference frames, isotropic space
interpretation, and tensor basics are all connected. When the tensor
was used in 3D flat space then the arbitrary reference frame made more
sense. Because time is unidirectional there is clearly an ambiguity in
choosing an arbitrary reference frame, and this conflict was somehow
washed clean. The tensor with arbitrary basis is about as close as you
can get to the isotropic claim.
That's completely wrong. Any tensor can be written in an
arbitrary basis. That doesn't have anything to do with isotropy.
Post by Tim Golden BandTech.com
Post by Daryl McCullough
(1) The covariance of the components of a tensor under changes
of coordinates, and (2) The invariance of a tensor field under
symmetry operations on the manifold. All tensors satisfy (1).
But only in certain special cases do the tensors satisfy (2).
The distinction is sometimes called "passive" versus "active"
coordinate transformations, but the latter is not really
a coordinate transformation, it is a mapping from the manifold
to itself that can be *described* using coordinates.
This is new to me. I'll try to keep an open mind on this.
This is not the tensor that I have studied, where the arbitrary basis
is fundamental.
This was the point of the representation; the actual basis becomes
generalized and expressions can be constructed without regard for say
x,y,z type of coordinates, especially when the equations are all going
to be the same.
That can *always* be done. Things don't have to be isotropic to
be able to do that.
Post by Tim Golden BandTech.com
These become x0,x1,x2 and the indexing becomes
implied. Now, when we chuck t in there then yes, the symmetry is
broken,
That's right, there is no 4-dimensional rotational symmetry for
spacetime, but that has nothing to do with being able to use
tensors.

--
Daryl McCullough
Ithaca, NY
Tim Golden BandTech.com
2011-02-04 14:49:38 UTC
Permalink
Post by Daryl McCullough
Tim Golden BandTech.com says...
Post by Tim Golden BandTech.com
Post by Daryl McCullough
I don't think you know what you are talking about. The use
of 4-dimensional tensors doesn't imply invariance under 4-dimensional
rotations.
Originally, yes, it did.
No, it didn't. One of the uses of tensors is explicitly for describing
anisotropic media (for example, look at the section called
"Anisotropic Materials" on this page:http://en.wikipedia.org/wiki/Hooke%27s_law
Thanks for getting me to think about this, but I do not see that this
is in conflict with my statements. Within the context there is stress
and strain which relate to the force and displacement of a material in
connection with
F = k x
and the idea that a material might have another elasticity component
in another direction such as
F2 = k2 x2
is appropriate to the tensor usage. Now, when this material undergoes
a coordinate transformation its properties will be preserved, so long
as they were entered correctly in the first place. Still, I do suppose
that in the real world trouble would creep in, so that by presuming
that a material's elasticities are fully explained as
(F1, F2, F3) = (k1 x1, k2 x2, k3 x3)
could be problematic, especially if the orientation of maximum
elasticity was not one of the original figures. This I would call the
orthogonal assumption; that this is a complete definition of a
material. Well, here we've gone by the most simplistic theories and
would also have to admit that nonlinear troubles lay about which
include the failure of the material to return to its original
configuration, though the puzzle of the cartesian representation as a
full quality representation does seem to be beneath those concerns.

Suppose for instance that we were to take a sphere of wood. We would
likely find it less elastic along the grain than accross it. If we
were to take the sample and arbitrarily take its reference frame
without one of the axes being along the grain then we will miss this
minimum, and might possibly arrive at an isotropic assumption. For
instance the first axis of testing of this material(and I do presume a
clean mathematical translation) is 45 degrees to the grain. The second
axis is orthogonal to this first and again at 45 degrees to the grain;
the third axis is orthogonal to the first two and again is 45 degrees
to the grain; such that if there were a cube of wood the grain would
lay along a diagonal to the cube which is the reference frame, and we
then were to carve the sphere.

We should readily admit that this attempt at an accurate portrayal of
this material is inadequate, for should the wood behave symmetrically
along these references then the figures characterizing it will be
identical under the chosen reference frame, and I do believe that this
is true generally.

What this means is that even for a system which may contain an
adequate orthogonal representation if the original choices were not
made correctly then its representation under transformation is
likewise flawed, for we have just experimentally arrived at a tensor
representation of an anistropic material that appears to be
isotropic.

This I will argue is merely another failing of the cartesian
assumption, and we do see it rear its head in some interesting places,
such as crytalline lattice construction, electron orbital solutions,
and likely more.
Post by Daryl McCullough
Post by Tim Golden BandTech.com
I admit that relativity theory does not use it this way and so
the relativistic usage is only a pseudotensor.
I think you are confused. The metric tensor is a tensor, not
a pseudotensor.
Well the truth here is that I'm not using the formal meaning of
pseudotensor, and would happily call what I just derived another one,
for the claims that the representation did start out to presume are
not necessarily guaranteed. Perhaps here even I operate on another
failed presumption. It is best to keep these arguments open, and also
to return to the fundamental core of the arguments as much as
possible. Here much of the higher level math fails, for it has made
its money by tendrilling out away from that core as much as possible
in order to make room for so many PhD's.
Post by Daryl McCullough
Often, pseudotensors arise in *nonrelativistic* physics, but they
become full-fledged tensors in relativistic physics. For example,
the magnetic field B is not a tensor, but the full electromagnetic
tensor F^ij is. For another example, angular momentum is not a tensor,
but the relativistic generalization *is*.
Post by Tim Golden BandTech.com
Still, the issue of relative reference frames, isotropic space
interpretation, and tensor basics are all connected. When the tensor
was used in 3D flat space then the arbitrary reference frame made more
sense. Because time is unidirectional there is clearly an ambiguity in
choosing an arbitrary reference frame, and this conflict was somehow
washed clean. The tensor with arbitrary basis is about as close as you
can get to the isotropic claim.
That's completely wrong. Any tensor can be written in an
arbitrary basis. That doesn't have anything to do with isotropy.
Well, I don't mean to pollute the argument, but perhaps to keep on
course with what I've already written it would be wise to consider
here a material that would have two maxima of elasticity which are not
perpendicular to each other and to consider whether such a material
can be accurately represented by an orthogonal representation. Here we
would enter into a skewed system, and I do see that this is a bit far
away from where we started, but you are of the advanced sort that
could consider such a thing. Anyway, back to my own defense, well, in
some ways I should not write any more, for we now have a claimed
instance of an anisotropic behavior being describes as an isotropic
one.

In essence what I may be doing is challenging the very word
'isotropic' as an invalid construction. Especially with the usage or
real values beneath a representation already there exists a
bilaterally asymmetry within the representation. This is the opening
that I seem to be driving toward now. That it could line up with the
quantum theories which do apparently rely upon high dimensional
solutions is encouraging, though i have to admit that I have only the
slightest idea what they are talking about.

You see there are holes, and when we go to fill them there is nothing
there. We must construct, and in order to construct we must willingly
break the existing claims.

Previously you mentioned a tensor usage where the 'dimensions' of the
tensor are pressure, volume, and temperature. Do you have any clean
links?

- Tim
Post by Daryl McCullough
Post by Tim Golden BandTech.com
Post by Daryl McCullough
(1) The covariance of the components of a tensor under changes
of coordinates, and (2) The invariance of a tensor field under
symmetry operations on the manifold. All tensors satisfy (1).
But only in certain special cases do the tensors satisfy (2).
The distinction is sometimes called "passive" versus "active"
coordinate transformations, but the latter is not really
a coordinate transformation, it is a mapping from the manifold
to itself that can be *described* using coordinates.
This is new to me. I'll try to keep an open mind on this.
This is not the tensor that I have studied, where the arbitrary basis
is fundamental.
This was the point of the representation; the actual basis becomes
generalized and expressions can be constructed without regard for say
x,y,z type of coordinates, especially when the equations are all going
to be the same.
That can *always* be done. Things don't have to be isotropic to
be able to do that.
Post by Tim Golden BandTech.com
These become x0,x1,x2 and the indexing becomes
implied. Now, when we chuck t in there then yes, the symmetry is
broken,
That's right, there is no 4-dimensional rotational symmetry for
spacetime, but that has nothing to do with being able to use
tensors.
--
Daryl McCullough
Ithaca, NY
Daryl McCullough
2011-02-04 16:44:17 UTC
Permalink
Tim Golden BandTech.com says...
Post by Tim Golden BandTech.com
Previously you mentioned a tensor usage where the 'dimensions' of the
tensor are pressure, volume, and temperature. Do you have any clean
links?
Here's a paper that uses a similar approach:
http://www.institutzamatematika.com/images/3/33/Trencevski_Mijatovic.pdf

--
Daryl McCullough
Ithaca, NY
BURT
2011-02-04 17:36:45 UTC
Permalink
Post by Daryl McCullough
Tim Golden BandTech.com says...
Post by Tim Golden BandTech.com
Previously you mentioned a tensor usage where the 'dimensions' of the
tensor are pressure, volume, and temperature. Do you have any clean
links?
Here's a paper that uses a similar approach:http://www.institutzamatematika.com/images/3/33/Trencevski_Mijatovic.pdf
--
Daryl McCullough
Ithaca, NY
The curve is part of gravity. Einstein's theory is incomplete.

Mitch Raemsch
Tim Golden BandTech.com
2011-02-06 15:46:28 UTC
Permalink
Post by Daryl McCullough
Tim Golden BandTech.com says...
Post by Tim Golden BandTech.com
Previously you mentioned a tensor usage where the 'dimensions' of the
tensor are pressure, volume, and temperature. Do you have any clean
links?
Here's a paper that uses a similar approach:http://www.institutzamatematika.com/images/3/33/Trencevski_Mijatovic.pdf
--
Daryl McCullough
Ithaca, NY
OK Daryl. Thanks for this. I'll have to revise my view. Perhaps I have
misled myself.
I do still believe that it is an odd position to hold that the linear
algebra which does allow conservative projections should not be used,
but this is all fine. Existing theory works with structured spacetime
then, and I have just been misled by imposing the properties of say a
standard Euclidean 3D form (isotropic) onto the 4D representation,
which is certainly very wrong if the information you provide is
accurate.

So, the forms which index components into x0,x1,x2,x3 don't really
care if these x are uniquely defined... this bit does still deserve
some criticism, but I have to leave the criticism at that for now.
Note that back when (x,y,z) became x0,x1,x2 the result was quite a
different beast, and that the concept of a relative reference frame
does not extend so cleanly as it did when the system was pure
geometry.

There is attention paid to the arbitrary basis within tensor theory,
and I am still attempting to resolve this with the relative reference
frame and isotropic behaviors versus structural issues. I guess maybe
rather than try to keep this thread alive I should make another run at
this when I've gained some fresh perspective. I do hope that I can get
your participation again and I appreciate you taking time here to post
in detail.

Thanks Daryl.

- Tim

shuba
2011-02-04 17:57:06 UTC
Permalink
Post by Tim Golden BandTech.com
Post by shuba
Space is isotropic for both Newtonian physics and special relativity.
Experimentally, it's true to within some rather tight error bars, both
locally and at cosmological scales.
   http://prl.aps.org/abstract/PRL/v57/i25/p3125_1
   http://prl.aps.org/abstract/PRL/v54/i22/p2387_1
   http://prl.aps.org/abstract/PRL/v42/i9/p549_1
   http://prl.aps.org/abstract/PRL/v90/i20/e201101
Access to these articles requires a membership. I cannot access these
docs.
You can read the abstracts and note the number of citations. These are
serious, vetted experimental results which are completely at odds with
your uninformed opinions and personal definitions. If you really want to
see the full papers, there are several potential options, such as finding
a library which provides free access. I don't particularly recommend that
you bother with the full papers, since your understanding of fundamental
terms and concepts is so utterly muddled.


---Tim Shuba---
mpc755
2011-01-31 14:58:17 UTC
Permalink
Post by Tom Roberts
Post by Alen
If the global manifold is
everywhere in spacetime, independently of the presence of
any test object, then I think we can forget about any notion
of a 'force field' picture of gravitation,
Not true. EVERY currently accepted theory of physics is based on a manifold,
which models either space or space-time. This includes all models in which
gravity is a force (e.g. Newtonian mechanics, the various field theories of
gravity, etc.). It also includes GR, in which gravity is not a force.
        A field is necessarily a field on a manifold -- that's what the
        word means (in this context).
Post by Alen
If, however, the manifold is being temporarily created by the
gravitational interaction [...]
You need to learn what a manifold actually is. You use the word in wildly
incorrect ways. This will require more precise thinking on your part, and a
STUDY of the literature to learn how the nomenclature is actually used.
You also need to recognize the difference between world and model. Manifolds and
fields are parts of the MODEL, not the world.
Tom Roberts
Displaced aether is part of the Universe.
Tim Golden BandTech.com
2011-01-28 13:56:22 UTC
Permalink
Post by Koobee Wublee
Post by Tim Golden BandTech.com
General Relativity claims that the mass of a body causes spatial
curvature, thus altering what to an inertial body would see as its
straight line path.
Gauss was the first to see a curved space. Riemann was the first to
mathematically model curved space. Riemann was also the first to
suggest a connection of gravitation and curved space but failed to
find any connection. If Riemann were to be born a few decades later,
he would no doubt find the connection in curved space and time.
<shrug>
So, yes, spatial curvature alone does not result in gravitation. You
only need curved time or gravitational time dilation. Thus, the
following spacetime is the simplest form that degenerates into
Newtonian law of gravity. <shrug>
ds^2 = c^2 (1 – 2 U) dt^2 – dr^2 – r^2 dO^2
Where
** U = G M / c^2 / r
** dO^2 = dLatitude^2 + cos^2(Latitude) dLongitude^2
Of course, the metric above would not satisfy the man-made Ricci
tensor in free space, and the Schwarzschild metric is not the only one
that degenerates into Newtonian law of gravity either. What else is
new? <shrug>
As we consider time within this context I think it is practical to use
a real example. From the wikipedia I quote:
"Equation (4) has been used to evaluate the time dilation
experienced by the satellites of the GPS global positioning system.
The increase in the rate of the satellite-borne clocks is about 38
microseconds per day.[15]"
- http://en.wikipedia.org/wiki/Time_dilation

So the effects of time on a GPS satellite are barely felt, while the
spatial effects are quite pronounced, for supposedly if we remove the
spatial curvature then the satellite will fly off in a straight line,
since this new theory has replaced Newtonian gravity completely.

I do hope you see the rub that I am getting at. If the satellite is
merely taking its inertial path, since no propellant is generally
required, and this path is one of the space's neutral paths, then
wouldn't we see light taking that very same path? This would be the
extensive form of the curved space claims, for when a space is so
deformed then the objects in it cannot be aware of such curvature.
This would be the proper effect of a truly curved space. I am becoming
inKleined to consider more dimensions to resolve this conflict.

Thanks Koobee for your equations, but I do feel that you have dodged
the simplicity of the argument that I am making. You start by arguing
that I have overlooked time, but upon incorporating it we are merely
looking at a very small effect. If the actual spatial curvature is
this small then it is not enough to explain Newtonian gravity. Again
though, I am open to having made a mistake, and do hope that you will
continue onward with your argument. I see your equations are already
fitting the satellite format, and look fairly consistent with the time
dilation link that I gave. The crux of the argument that I gave is in
the straight line interpretation, which suggests that if we were to
extend a tape measure out from this satellite that it would bow with
the earth and still appear straight. In effect the satellite should
see itself along this tape measure if spatial curvature explains its
orbit, and its orbit is stable. This is how far the claim of spatial
curvature ought to go, but as far as I understand it is not taken this
far. That the earth is flat ought to be a revivalist theory under
Einstein's equations within the accepted interpretation.

- Tim
Tom Roberts
2011-01-29 00:30:22 UTC
Permalink
Post by Tim Golden BandTech.com
As we consider time within this context I think it is practical to use
"Equation (4) has been used to evaluate the time dilation
experienced by the satellites of the GPS global positioning system.
The increase in the rate of the satellite-borne clocks is about 38
microseconds per day.[15]"
- http://en.wikipedia.org/wiki/Time_dilation
So the effects of time on a GPS satellite are barely felt,
NONSENSE! That 38 us/day, if left uncorrected, would make the GPS positioning
service completely and utterly unusable.
Post by Tim Golden BandTech.com
while the
spatial effects are quite pronounced, for supposedly if we remove the
spatial curvature then the satellite will fly off in a straight line,
More nonsense.

As I have said many times before, it is the curvature in spaceTIME that is
important. Indeed, in the Newtonian approximation to GR, space is exactly flat,
yet objects fall and satellites orbit.

The orbit of a GPS satellite has a radius of 20,000 km + 6,4000 km, or less than
0.1 light-second; its period is 12 hours. So during one orbit the satellite
travels along one turn of a helical path with radius 0.1 light-second and length
along the time axis of 43,200 light seconds. That is, it deviates from a
straight line through spaceTIME by about 2 parts per million. The spatial
curvature is MUCH less than that (using the usual, appropriate coordinates).
Post by Tim Golden BandTech.com
I do hope you see the rub that I am getting at.
The "rub" is that you simply do not understand GR. Until you sit down and STUDY
it you will remain mystified, and will keep making mistakes.


Tom Roberts
Koobee Wublee
2011-01-29 09:18:10 UTC
Permalink
Post by Tom Roberts
NONSENSE! That 38 us/day, if left uncorrected, would make the GPS positioning
service completely and utterly unusable.
That is indeed nonsense. If not corrected, it would not affect
anything as long as the following criterions are met:

** All satellites have the same frequency/clock driving the calendar
time.

** All satellites are synchronized to the same calendar time.

** Each satellite knows its position at any time.

** Each GPS receiver acquires the almanac information from at least 4
satellites.
Post by Tom Roberts
More nonsense.
Excuse me! <shrug>
Post by Tom Roberts
As I have said many times before, it is the curvature in spaceTIME that is
important.
To be more precise, all you need is gravitational time dilation for
the phenomena in gravitation. <shrug>
Post by Tom Roberts
Indeed, in the Newtonian approximation to GR, space is exactly flat,
yet objects fall and satellites orbit.
Newtonian mechanics. <shrug>
Post by Tom Roberts
The orbit of a GPS satellite has a radius of 20,000 km + 6,4000 km, or less than
0.1 light-second; its period is 12 hours. So during one orbit the satellite
travels along one turn of a helical path with radius 0.1 light-second and length
along the time axis of 43,200 light seconds. That is, it deviates from a
straight line through spaceTIME by about 2 parts per million. The spatial
curvature is MUCH less than that (using the usual, appropriate coordinates).
At the end of the day, all you need are these four conditions
mentioned earlier in this very same post. <shrug>
Post by Tom Roberts
Post by Tim Golden BandTech.com
I do hope you see the rub that I am getting at.
The "rub" is that you simply do not understand GR. Until you sit down and STUDY
it you will remain mystified, and will keep making mistakes.
It helps if you actually understands the mathematics involved in GR.
<shrug> No mathemagics, please.
Tim Golden BandTech.com
2011-01-31 22:48:05 UTC
Permalink
Post by Tom Roberts
Post by Tim Golden BandTech.com
As we consider time within this context I think it is practical to use
   "Equation (4) has been used to evaluate the time dilation
experienced by the satellites of the GPS global positioning system.
The increase in the rate of the satellite-borne clocks is about 38
microseconds per day.[15]"
 -http://en.wikipedia.org/wiki/Time_dilation
So the effects of time on a GPS satellite are barely felt,
NONSENSE! That 38 us/day, if left uncorrected, would make the GPS positioning
service completely and utterly unusable.
Post by Tim Golden BandTech.com
while the
spatial effects are quite pronounced, for supposedly if we remove the
spatial curvature then the satellite will fly off in a straight line,
More nonsense.
As I have said many times before, it is the curvature in spaceTIME that is
important. Indeed, in the Newtonian approximation to GR, space is exactly flat,
yet objects fall and satellites orbit.
The orbit of a GPS satellite has a radius of 20,000 km + 6,4000 km, or less than
0.1 light-second; its period is 12 hours. So during one orbit the satellite
travels along one turn of a helical path with radius 0.1 light-second and length
along the time axis of 43,200 light seconds. That is, it deviates from a
straight line through spaceTIME by about 2 parts per million. The spatial
curvature is MUCH less than that (using the usual, appropriate coordinates).
Post by Tim Golden BandTech.com
I do hope you see the rub that I am getting at.
The "rub" is that you simply do not understand GR. Until you sit down and STUDY
it you will remain mystified, and will keep making mistakes.
Tom Roberts
Not at all Tom. You've stated it perfectly:
"...it deviates from a straight line through spaceTIME
by about 2 parts per million. The spatial curvature
is MUCH less than that..."
Yet the straight line interpretation will have that satellite heading
away from the earth, and at roughly two circumferences per day. So it
doesn't take much to get an orbit. Fine. Gravity is weak at large
distance.

I do like that you have figures here, and I was just trying to get
that elevation figure that you've filled in, though my understanding
is that the circumference of the earth is roughly 4E7 meters, which
doesn't seem to be agreeing so well with your figures.

Without the curvature the GPS satellite will take a straight line
under GR's gravity/spacetime replacement theory. Here if we use your
own radius figure of roughly 26.4E6 meters, my computer tells me that
there is a curvature of 1.9E-8 meters per meter, where this figure is
the Gallilean motion normal to the inertial path. This is simply based
on the radius of the path. Still, this curvature is strictly a
function of the satellite's velocity. For instance when we replace the
satellite with a photon we might not even resolve it with a 64 bit
float.
My initial point is that this spatial curvature is a function of the
object's velocity. If the curvature was constant then the light would
travel the same path as the satellite, and the GR interpretation of
curved space would be more coherent to the Newtonian mind. This detail
and its resolution within standard interpretations of the GR math is
really what I started out discussing. We are constantly caught in
confusion as we discuss 'straight' paths, and curvatures and so forth
from Gallilean, then SR, and then GR points of view. I have to admit
that my own usage is poor here, but that the simple identification of
the inclusion of time within the curvature may not be quite enough
either.

- Tim
Tom Roberts
2011-02-02 21:37:31 UTC
Permalink
Post by Tim Golden BandTech.com
The orbit of a GPS satellite [...] a helical path [...] That is, it deviates from a
straight line through spaceTIME by about 2 parts per million.
Yet the straight line interpretation will have that satellite heading
away from the earth, and at roughly two circumferences per day.
No. You don't understand this at all.

Inasmuch as we consider just the earth and satellite, the earth is traversing
through spacetime on a straight line along the time axis, and the satellite is
traversing along a helix with its axis centered on the earth's trajectory along
the time axis, with a radius of ~0.1 light-second, and with a period of 12
light-hours. That helix NEVER "heads away" from the earth, it CIRCLES the earth,
because earth and satellite traverse the time axis together.
Post by Tim Golden BandTech.com
Without the curvature the GPS satellite will take a straight line
under GR's gravity/spacetime replacement theory.
I have no idea what you mean by "GR's gravity/spacetime replacement theory". GR
is a theory of gravity, and no "replacement" is needed. GR supplants Newtonian
gravitation, which is not really a "replacement", as NG remains valid within a
limited but quite useful domain.
Post by Tim Golden BandTech.com
[...] Still, this curvature is strictly a
function of the satellite's velocity.
The "curvature" of the satellite's path is; the curvature of spacetime is not.
Post by Tim Golden BandTech.com
For instance when we replace the
satellite with a photon we might not even resolve it with a 64 bit
float.
You still don't get it. The "photon" is not bound by the earth's gravity, and
travels out into space. The satellite is bound to the earth by gravity, and
ORBITS. This OUGHT to be obvious.
Post by Tim Golden BandTech.com
My initial point is that this spatial curvature is a function of the
object's velocity. [...]
And that point is wrong. As is just about everything else you have said in this
thread. As I said before, the spatial curvature is negligible, and the
properties of spacetime do not depend in any non-negligible way on the satellite
(or its velocity).


Tom Roberts
Tim Golden BandTech.com
2011-02-03 14:42:51 UTC
Permalink
Post by Tom Roberts
Post by Tim Golden BandTech.com
The orbit of a GPS satellite [...] a helical path [...] That is, it deviates from a
straight line through spaceTIME by about 2 parts per million.
Yet the straight line interpretation will have that satellite heading
away from the earth, and at roughly two circumferences per day.
No. You don't understand this at all.
Inasmuch as we consider just the earth and satellite, the earth is traversing
through spacetime on a straight line along the time axis, and the satellite is
traversing along a helix with its axis centered on the earth's trajectory along
the time axis, with a radius of ~0.1 light-second, and with a period of 12
light-hours. That helix NEVER "heads away" from the earth, it CIRCLES the earth,
because earth and satellite traverse the time axis together.
I was speaking of the inertial path if we remove gravity; remove the
curvature theory that is GR. I admit that perhaps my language should
be even more explicit, but it is this sensibility and context from
which I opened this thread; that if we remove the curvature of GR that
the objects will simply take inertial paths; the paths that they take
in GR are claimed to be a version of these by introducing curvature of
space and time.
Post by Tom Roberts
Post by Tim Golden BandTech.com
Without the curvature the GPS satellite will take a straight line
under GR's gravity/spacetime replacement theory.
I have no idea what you mean by "GR's gravity/spacetime replacement theory". GR
is a theory of gravity, and no "replacement" is needed. GR supplants Newtonian
gravitation, which is not really a "replacement", as NG remains valid within a
limited but quite useful domain.
Boy, you are stretching here. This interpretation is exactly the claim
of GR within its own standard interpretation; that no actual force
between massive objects exists; that instead these massive objects
alter the qualities of space and time around them.

That the replacement theory (GR) mimics the old theory is accurate,
but you are backpeddling here. That you would refute that GR replaces
Newtonian gravity in modernity is a ridiculous stance for you who
supports GR.
Post by Tom Roberts
Post by Tim Golden BandTech.com
[...] Still, this curvature is strictly a
function of the satellite's velocity.
The "curvature" of the satellite's path is; the curvature of spacetime is not.
Ahh... Perhaps you Tom have not fully absorbed the meaning of GR
though it has been literally stated by many and numerously. The
curvature of the satellites path is the curvature of spacetime. If
this is not the case then please do find this nuance within the
existing theory. I entered a quote at the OP that I believe was a fine
instance and that you are betraying here.
Post by Tom Roberts
Post by Tim Golden BandTech.com
For instance when we replace the
satellite with a photon we might not even resolve it with a 64 bit
float.
You still don't get it. The "photon" is not bound by the earth's gravity, and
travels out into space. The satellite is bound to the earth by gravity, and
ORBITS. This OUGHT to be obvious.
Wrong again. GR does place claims on the curvature of photons.
Post by Tom Roberts
Post by Tim Golden BandTech.com
My initial point is that this spatial curvature is a function of the
object's velocity.  [...]
And that point is wrong. As is just about everything else you have said in this
thread. As I said before, the spatial curvature is negligible, and the
properties of spacetime do not depend in any non-negligible way on the satellite
(or its velocity).
Tom Roberts
Perhaps you and I had just better agree to disagree. I will attempt to
disregard further posts from you here.

- Tim
c***@physics.ucdavis.edu
2011-01-29 02:20:09 UTC
Permalink
In sci.astro Tim Golden BandTech.com <***@yahoo.com> wrote:

[...]
Post by Tim Golden BandTech.com
As we consider time within this context I think it is practical to use
"Equation (4) has been used to evaluate the time dilation
experienced by the satellites of the GPS global positioning system.
The increase in the rate of the satellite-borne clocks is about 38
microseconds per day.[15]"
- http://en.wikipedia.org/wiki/Time_dilation
So the effects of time on a GPS satellite are barely felt, while the
spatial effects are quite pronounced, for supposedly if we remove the
spatial curvature then the satellite will fly off in a straight line,
This is wrong for two reasons.

1. It's true that the GPS time dilation is small. But the deviation of
the satellite from a straight line is also very small. You're getting
your units mixed up -- you're dropping factors of the speed of light.

The time dilation is small because you're comparing time to time --
a change in time of 38 ms in a time of one day. Obviously, you have
to make that kind of comparison; if the time dilation were 38 ms
in one nanosecond, it wouldn't be small, it would be huge.

If you want to make a corresponding estimate of the deviation of
the orbit from a straight line, you also have to compare like to
like -- times to times or distances to distances. That's not hard,
because relativity tells you how to convert distances to times.
A GPS satellite has a period of 12 hours. In that time, it moves in
an orbit with a circumference of about 170,000 km. But 170,000 km
is a bit more than one-half light second. So the deviation of the
orbit from a straight line is only about a half second in 12 hours,
roughly one part in 80,000. That's pretty straight.

2. It's not true that if we remove the spatial curvature, the path
would be a straight line. To a pretty good approximation, the purely
spatial curvature -- the curvature of space at a fixed time -- around
the Earth is zero. The relevant curvature is neither "purely spatial"
nor "purely time" -- it's the curvature in, for example, the r--t
(radius--time) plane in spacetime.

I'm a little confused about why you are arguing about this, though.
You can, after all, *calculate* the geodesics in a spacetime given
a curvature, and the results agree with what we see. When a
concrete (and not terribly hard) mathematical calculation gives
a result that you find unintuitive, you should perhaps question
your intuition.
Post by Tim Golden BandTech.com
I do hope you see the rub that I am getting at. If the satellite is
merely taking its inertial path, since no propellant is generally
required, and this path is one of the space's neutral paths, then
wouldn't we see light taking that very same path?
Because the relevant paths are paths in spacetime, not paths
in space. A beam of light and a satellite start off at different
speeds. But a speed is a direction in spacetime (it's a "distance
in space" divided by a "distance in time"). If two objects start
off in different directions, it's hardly surprising that they take
different paths.

The questions you ask are legitimate ones. But they're not
mysterious; they just require a bit more than first impressions
and guesses about what general relativity says. If you really
want thorough answers, you'll need to buckle down and actually
learn some relativity, math and all. The sci.physics FAQs at
math.ucr.edu/home/baez/physics/Administrivia/rel_booklist.html
have a good book list. Give it a try.

Steve Carlip
Tim Golden BandTech.com
2011-01-31 16:13:36 UTC
Permalink
Post by c***@physics.ucdavis.edu
[...]
Post by Tim Golden BandTech.com
As we consider time within this context I think it is practical to use
   "Equation (4) has been used to evaluate the time dilation
experienced by the satellites of the GPS global positioning system.
The increase in the rate of the satellite-borne clocks is about 38
microseconds per day.[15]"
 -http://en.wikipedia.org/wiki/Time_dilation
So the effects of time on a GPS satellite are barely felt,  while the
spatial effects are quite pronounced, for supposedly if we remove the
spatial curvature then the satellite will fly off in a straight line,
This is wrong for two reasons.
1.  It's true that the GPS time dilation is small.  But the deviation of
the satellite from a straight line is also very small.  You're getting
your units mixed up -- you're dropping factors of the speed of light.
The time dilation is small because you're comparing time to time --
a change in time of 38 ms in a time of one day.  Obviously, you have
to make that kind of comparison; if the time dilation were 38 ms
in one nanosecond, it wouldn't be small, it would be huge.
OK, that's microseconds, and with a metric that uses
c dt
we have
(38 E-6)(3 E8) = 1.14 E4 meters,
or about ten kilometers of 'timelike' contribution. This is not much.
Post by c***@physics.ucdavis.edu
If you want to make a corresponding estimate of the deviation of
the orbit from a straight line, you also have to compare like to
like -- times to times or distances to distances.  That's not hard,
because relativity tells you how to convert distances to times.
A GPS satellite has a period of 12 hours.  In that time, it moves in
an orbit with a circumference of about 170,000 km.  But 170,000 km
is a bit more than one-half light second.  So the deviation of the
orbit from a straight line is only about a half second in 12 hours,
roughly one part in 80,000.  That's pretty straight.
Not sure how you got here, since we started out with 38 microseconds
per day.
I guess this is the SR computation based on velocity.
Post by c***@physics.ucdavis.edu
2.  It's not true that if we remove the spatial curvature, the path
would be a straight line.  To a pretty good approximation, the purely
spatial curvature -- the curvature of space at a fixed time -- around
the Earth is zero.  The relevant curvature is neither "purely spatial"
nor "purely time" -- it's the curvature in, for example, the r--t
(radius--time) plane in spacetime.
Well, here I am definitely in disagreement with you, and I have to
admit that it is difficult to argue with such a big name, but then, we
are hopefully being scientific and should get by that layer. So I must
argue with you here as if you were anyone else. The object of removing
the spatial curvature is a portion of the standard intrepretation of
GR, which states that the satellite which uses no propulsion is on its
inertial course, so that should we remove the curvature what remains
is traditional inertial motion in a straight line, and these paths are
straight regardless of the velocity of the object in question. This is
tantamount to the removal of gravity, which GR explains via this
curvature mechanism. Without gravity objects move in straight paths;
not orbitals. Under this awareness the spatial curvature of the
satellite orbiting the earth is quite impressive. Yes, it is
continuous in nature, but the captive object's positional freedom is
greatly altered.
Post by c***@physics.ucdavis.edu
I'm a little confused about why you are arguing about this, though.
You can, after all, *calculate* the geodesics in a spacetime given
a curvature, and the results agree with what we see.  When a
concrete (and not terribly hard) mathematical calculation gives
a result that you find unintuitive, you should perhaps question
your intuition.
Well, I agree here, and am hoping that you can challenge my intuition
too. Still, this challenge does not merely degrade to copying someone
else's work. This mimicry reflex is so strong in humans, and
unfortunately it may be the case that these abilities to manipulate
our intuition should have been built when we were younger. To what
degree I am wired into Newtonian thought I am unsure, but that is
where I am most comfortable. I do hope for a semiclassical theory that
will make more sense than GR. I do more than just hope for this
thing.
Post by c***@physics.ucdavis.edu
Post by Tim Golden BandTech.com
I do hope you see the rub that I am getting at. If the satellite is
merely taking its inertial path, since no propellant is generally
required, and this path is one of the space's neutral paths, then
wouldn't we see light taking that very same path?  
Because the relevant paths are paths in spacetime, not paths
in space.  A beam of light and a satellite start off at different
speeds.  But a speed is a direction in spacetime (it's a "distance
in space" divided by a "distance in time").  If two objects start
off in different directions, it's hardly surprising that they take
different paths.
Wow. Thanks Steve for such a detailed reply. I admit that I do see the
c factor in the metric, though it is tough for me to see velocity
within the (x,y,z,t) coordinates and see any curvature. I agree about
the different paths, and we could set the initial conditions to any
direction for a low mass satellite orbiting a massive object, and any
velocity, but I am trying to distinguish the orbital path of the
satellite and compare it with itself at another velocity, so for
instance your beam of light taking the same path as the satellite. I
do believe that the standard language of the interpretation of
spacetime curvature as a Newtonian gravity replacement does deserve
this additional level of awareness; that the velocity matters. Mainly
this is important because in the inertial system velocity doesn't
matter as to the path of an object; they just travel straight lines. I
admit that I do need to learn more GR. I was just reading more of AE's
1920 Relativity The Special and General Theory and am having a hell of
a difficult time prying those mollusks open. Thanks so much Steve for
you response here.

- Tim
Post by c***@physics.ucdavis.edu
The questions you ask are legitimate ones.  But they're not
mysterious; they just require a bit more than first impressions
and guesses about what general relativity says.  If you really
want thorough answers, you'll need to buckle down and actually
learn some relativity, math and all.  The sci.physics FAQs at
math.ucr.edu/home/baez/physics/Administrivia/rel_booklist.html
have a good book list.  Give it a try.
Steve Carlip
Eric Gisse
2011-01-29 08:18:24 UTC
Permalink
Post by Tim Golden BandTech.com
Post by Tim Golden BandTech.com
General Relativity claims that the mass of a body causes spatial
curvature, thus altering what to an inertial body would see as its
straight line path.
Gauss was the first to see a curved space.  Riemann was the first to
mathematically model curved space.  Riemann was also the first to
suggest a connection of gravitation and curved space but failed to
find any connection.  If Riemann were to be born a few decades later,
he would no doubt find the connection in curved space and time.
<shrug>
So, yes, spatial curvature alone does not result in gravitation.  You
only need curved time or gravitational time dilation.  Thus, the
following spacetime is the simplest form that degenerates into
Newtonian law of gravity.  <shrug>
ds^2 = c^2 (1 – 2 U) dt^2 – dr^2 – r^2 dO^2
Where
**  U = G M / c^2 / r
**  dO^2 = dLatitude^2 + cos^2(Latitude) dLongitude^2
Of course, the metric above would not satisfy the man-made Ricci
tensor in free space, and the Schwarzschild metric is not the only one
that degenerates into Newtonian law of gravity either.  What else is
new?  <shrug>
As we consider time within this context I think it is practical to use
   "Equation (4) has been used to evaluate the time dilation
experienced by the satellites of the GPS global positioning system.
The increase in the rate of the satellite-borne clocks is about 38
microseconds per day.[15]"
 -http://en.wikipedia.org/wiki/Time_dilation
So the effects of time on a GPS satellite are barely felt [...]
What's 50 microseconds/day in terms of distance?

Now tell me how long it would take before the system is completely
unusable.
Inertial
2011-01-26 23:33:43 UTC
Permalink
"Tim Golden BandTech.com" <***@yahoo.com> wrote in message news:454dbe9f-7f97-423c-89cb-***@u13g2000prd.googlegroups.com...

spaetime curvature doesn't REPLACE gravity .. it IS gravity.

Your question is nonsense, and your answer even more so

[snip nonsense]
mpc755
2011-01-26 23:47:50 UTC
Permalink
Post by Inertial
spaetime curvature doesn't REPLACE gravity .. it IS gravity.
What occurs physically in nature in order for spacetime curvature to
cause gravity?

Now, I realize another poster is unable to understand I am asking you
this question because I know you can't answer it.

The reason you are unable to answer it is because you are unable or
unwilling to understand spacetime curvature is displaced aether.

Dark matter IS aether.
Aether has mass.
Aether is displaced by matter.
Displaced aether is not at rest.
Displaced aether exerts force towards matter.
Force exerted towards matter by aether displaced by matter is gravity.
The rate at which an atomic clock ticks is determined by the force of
the aether in which it exists.
Igor
2011-01-28 22:05:34 UTC
Permalink
Post by Tim Golden BandTech.com
However, the spatial curvature is regarded as a
constant regardless of a body's velocity.
This is not correct. In general, the stress-energy tensor is
dependent on both mass density and the relative velocity components of
the source.
Koobee Wublee
2011-01-29 09:23:42 UTC
Permalink
Post by Igor
Post by Tim Golden BandTech.com
However, the spatial curvature is regarded as a
constant regardless of a body's velocity.
This is not correct. In general, the stress-energy tensor is
dependent on both mass density and the relative velocity components of
the source.
You obviously don’t know what you are talking about. The stress
energy tensor is zero for simple Newtonian mechanics. It does not
depend on the mass density, etc. <shrug>

Remember that the Ricci tensor = 0 in free space. <shrug>
Androcles
2011-01-29 09:53:09 UTC
Permalink
Post by Igor
Post by Tim Golden BandTech.com
However, the spatial curvature is regarded as a
constant regardless of a body's velocity.
This is not correct. In general, the stress-energy tensor is
dependent on both mass density and the relative velocity components of
the source.
You obviously don’t know what you are talking about.
==========================================
The shaman Wublee (shaman by his own definition) OBVIOUSLY
doesn't know what he's babbling about. <shrug>

Electromagnetics don't mechanically radiate as waves.
Snip and hide from the facts you don't like, mechanical shaman.

It is hypothesized that light is a wave in the all-pervasive ectoplasm
called aether, analogous to sound energy being transmitted through
a material medium such as air, water, steel rails, etc. Paradoxically,
it is further hypothesized that the ectoplasm is dragged along by the
Earth in its orbit around the Sun to explain the null effect of the
Michelson interferometer, which necessarily implies friction between
the Earth and the mysterious ectoplasm, and turbulence as the Moon
stirs the mystical substance. This friction is totally absent, for it
would slow the planets in their orbits and cause them to fall into the
Sun, yet is present for the Earth to drag the ectoplasm along with it,
which is a paradox and a fallacy. The ghostly ectoplasm's sole
existence is for the transmission of light, it has no other detectable
physical properties whatsoever. It is therefore logical to conclude that
some other mechanism is responsible for the transmission of
electromagnetic energy.

"Ockham's razor, often expressed in Latin as the lex parsimoniae,
translating to law of parsimony, law of economy or law of succinctness, is a
principle which generally recommends selecting the competing hypothesis that
makes the fewest assumptions, when the hypotheses are equal in other
respects. For instance, they must both sufficiently explain available data
in the first place." - Wackypedia.

"A paradox must indicate a fallacy. Only priests in any religion or
shaman in any superstition would turn a blind eye to this paradox and
thus the fallacy itself in hoping to perpetuate their useless
positions in a society. <shrug>" -- Shaman Koobee Wublee, High Priest
of the Church of the Aetherialists.
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