Post by Tom RobertsPost by beda pietanzaPost by Tom Roberts1. There are no "fixed stars".
2. Stars visible from earth are part of the Milky Way galaxy,
WHICH IS ROTATING. There's nothing "fixed" about that.
3. Distant galaxies are MUCH less "fixed" than stars in the
Milky Way. They have relative velocities ranging up to a
substantial fraction of c.
Ancient astronomers thought some stars were "fixed", merely because
their VISIBLE motion is so small. We now know they are not "fixed" at all.
Proponents of "absolute motion" have NEVER presented a method to measure
you as usual throw smoke in the eye of the reader,
No. I merely tell it like it is.
Post by beda pietanzathe polaris is changing its position so slow that it will take millennia to be substituted
in its funtion as a North pole reference,
So it is not "fixed".
dear roberts,
you have been my best teacher, it may be time to pay you back,
even tough, you may not respond to this replay of mine, I will
answer you on every point, for my own sake
yes, polaris not fixed
nevertheless of stars has been used by sailor to determine their
position on the see, where no other reference was there, so their
apparent position is stable enough
Post by Tom RobertsPost by beda pietanzaso for our purpose that is not a problem.
Sure it is! -- it is NOT "fixed".
beda:
stable enough for our purpose, a couple of measurement in a short time von't see
any apparent change of the star position nor of its color
Post by Tom RobertsNope. Such a "check" can only determine your motion RELATIVE TO THAT
PARTICULAR STAR.
beda:
Hai,hai!, capital letters for a capital error, you taught me that physics is about
interaction that take place only locally, have changed your mind?
how can I interact locally with polaris 447 ly distant?
I am interacting only with the polaris incoming light that was emitted 447 years ago.
is light arriving now, at my local place, stable enough that I can use it as a reference?
yes, I think its speed is constant, its spectrum is constant, the direction it is coming from
is constant, therefore it is a good absolute reference moving at c versus me.
I am moving at an unknown absolute speed, versus a light coming whose speed is absolute c
two stable absolute speeds, make a fixed result in the shift of the spectrum of the
polaris light that I perceive,
if I change my absolute speed the change of the light spectrum I would perceive is only due
to the change of my absolute movement,
I still not know the value of my absolute movement, nor the entity of its absolute change, the only think I am sure of
is, that the change of the spectrum is due to my changing of my absolute speed.
Post by Tom RobertsPost by beda pietanzalight coming from a star like polaris, [...]
this proves that my absolute hidden movement exists.
Nope. It only shows your motion RELATIVE TO POLARIS.
Post by beda pietanzaone among many way to detect the absolute speed of a object in space (away from near masses)
is to measure the intensity of the incoming light from all the directions, when this is uniform we are at
rest vs that point in space, anything passing by us have an absolute speed vs us and the local space.
Nope. You are only measuring LIGHT INTENSITIES. This is incredibly
stupid as you take no account of the varying magnitudes of stars.
Post by beda pietanzaCMBR, the average uniformity of it from every direction of the universe, is a good reference in this.
Sure, you can measure your speed relative to the local CMBR dipole=0
frame. There is NOTHING "absolute" about that, you are just measuring
your speed relative to SOME OTHER LOCALLY INERTIAL FRAME.
beda:
you should not brink in some concepts that belong only to your theory, there are
not any frame there nor nature need them to do what it does, the only model valid
is the nature itself, we are talking here about how nature works at best we know
Post by Tom RobertsPost by beda pietanzait is matter of conventional agreement,
"Conventional" is not at all the same as "absolute". Just like "fantasy"
is not at all the same as "physics".
Post by beda pietanzato my opinion, and I am sure to many,
absolute movement is the one versus the entire universe taken as whole,
But how do you MEASURE that?
beda:
dear tom, we are such a small part of the universe, you told me that physics is
only about local interactions, you forgot that a proper use of our knowledge
has to include a picture of how the universal greatness works at a larger and larger scale
is there in the dept of space we may find that a object left there finds its way
pulled by forces coming from the surrounding masses, the unbalance of that forces
make the object move in some direction or another.
there may not be any place in the universe at perfect equilibrium, a residual unbalance
will be left and generate the rotational moving of the object to join to the totality
movement of the local large scale distributions of masses,
light speed isotropically moving at c may be impossible to find practically
but for sure the presence of matter close or far determine locally at small and/or
at large scale the light speed variation in space.
how we measure the absolute movement?
there are three local references, the local space (with its properties and unisotropies),
the local speed of light (locally) the entire universe as a whole (contrary to your opinion
it is apparently stable enough for our needs), before we go further into this issue you may need
to leave (at least for the time we debate ) apart your deceiving theoretical tools.
the best model in physics is the reality itself, wrong model send you into a dead end route
Post by Tom RobertsYou assume "the entire universe" has some sort of definite speed or
motion to be used as a reference -- astronomical observations show this
is simply not the case in the world we inhabit -- just about everything
is moving relative to just about everything else.
beda
of course, locally the ""so called ether"" participate to its movement,
even in a vortex you can be locally at rest with your near masses,
nevertheless it is the reference point for nature to set locally light and objects speeds
Post by Tom RobertsFor "absolute speed" to make sense, it must be possible to determine its
value at any location in the cosmos, and all objects with an "absolute
speed" of zero must be at rest relative to each other.
beda:
absolutely not true, I can be "at rest" versus the local space in my galaxy
at smaller scale versus any cluster of near masses and at same time participate
unaffected, with my galaxy to the larger scale rotating movement
Post by Tom RobertsAstronomical
observations show this simply does not happen in the world we inhabit.
Post by beda pietanzacondensed in the physical properties of the local space that makes, in that point, light speed
isotropically travel at c.
But light speed (in vacuum) is isotropically c relative to ANY locally
inertial frame. There's NOTHING "absolute" about that.
beda:
you should not use your theory to justify your theory, but facts and logic interpretation of facts
using common concepts , again frames prevents you to see the reality,
your frames are an anaformism of the reality and now you travel in a multidimensional
non existent space
Post by Tom RobertsAs usual, you are just repeating your personal fantasies and pretending
they are true. Don't expect me to respond further.
beda,
that is a pity, you helped me in the past, I could pay back, I instead will keep reading your posts
and if it is worth answer them
all the best
beda