Post by Ed LakePost by VolneyPost by VolneyPost by Ed LakePost by Ed LakeOver the years, I've accumulated a list of 12 major Time Dilation
experiments which CONFIRM that Time Dilation is REAL, and that
time does run at different rates for an object depending upon an
object's speed and its proximity to a gravitational mass.
Every competent physicist knows that, in terms of the essentially unique stationary temporal foliation near a large spherical massive body (corresponding to the Schwarzschild time coordinate), the rate of proper time (dtau/dt) for an object along any given path is different depending on the speed and the elevation of the object. That's what it means to say that clocks run at different rates depending on speed and elevation. No competent person disputes this, so all your years of accumulating lists of experimental evidence of this has been pointless. Again: No. One. Disputes. This.
"It may be your opinion the length of a second is variable, but actual
scientists have defined a second to be 9,192,631,770 cycles of a certain
frequency of a Cs atom. Variable length seconds make as little sense as
variable length meters or variable mass kilograms. "
That is the PROPER time, the clock used must be comoving and local to
the observer. Different observers on different paths can have different
values for their own proper times because the proper time of one is NOT
the proper time of the other, because the second observer's clock was
NOT comoving and local to the first observer (because it was comoving
and local to the second observer!
You are complicating something that is really very simple. A cesium atomic
clock will cycle 9,192,631,770 times per second whether there is an observer
next to it or not.
Locally, and in a frame in which the clock is stationary.
I'm talking about REALITY, not about mathematical models.
This IS reality. As in physics (not math). A Cs clock sitting there,
measuring seconds. Someone local to it will confirm it is accurate. Fly
by it at 0.5c, or view it from a gravity well, and it will be seen
ticking at the wrong rate. So I added the requirement "locally, and in
a frame where the clock is stationary." Is that too hard to understand?
Post by Ed LakePost by VolneyIf there is an observer next to it, the time becomes the "proper
time" for that observer.
Clocks always measure their own proper time.
If two clocks are side by side and one measures minutes to be longer
than the other, one or both of them are WRONG.
In this type of physics gedanken discussion, clocks are ideal, they are
accurate by definition. If something ticks at the wrong rate, it is not
a clock, as far as physics is concerned, even if it looks like a clock.
So for your two devices which look like a clock, one or both are NOT
clocks (in physics).
Post by Ed LakeIf "clocks always
measure their own proper time," then "proper time" has no meaning
IN REALITY.
Wrong, clocks, which are ideal in physics, measure their own proper
time. Things that look like clocks but aren't clocks, don't. Of course
in the real world, any physical clock has a margin of error in
measurement but it is assumed the error is smaller than other
measurement errors. If not, the measurement is invalid, and that "clock"
isn't useful as a clock.
Post by Ed LakePost by VolneyA different cesium atom clock that is moving 259,628 kilometers per second
faster than the first clock will measure ONE second in the time it takes the first
clock to measure TWO seconds. It makes no difference if there is anyone
around to make it their "proper time" or not.
And the first clock will measure ONE second in the time it takes the
second clock to measure TWO seconds.
Yes.
Post by VolneyThis is relative motion and time dilation according to Einstein.
It is time dilation according to Einstein. "Relative motion" requires qualifications.
No additional qualification needed. In the frame of the first, the
second is moving at +v. In the frame of the second, the first is moving
at -v. That is Galileo's relative motion. (Einstein not even needed for
that!)
Post by Ed LakePost by VolneyYou only need an observer when you want to COMPARE tick rates. And that is
typically done by starting with the two clocks together in front of the observer,
then moving one of the clocks away at high speed and then bringing the two clocks
back together again.
Now, that is the traveling twin gedanken, and that happens due to the
turnaround (acceleration). Time dilation as in the 1905 paper works
only when both clocks are inertial. Obviously a turnaround isn't inertial.
You are discussing mathematics. I am discussing REALITY.
This IS reality (physics). I didn't even mention math. This is done all
the time in things like muon storage rings, or CERN, where things go
round and round back to the origin, even if there are many bending
magnets (curving is acceleration) so that it's almost a circle. One
"twin" is a muon in the storage ring, the other a stationary muon at the
origin.
Post by Ed LakeWhen discussing
MATHEMATICS, you cannot cope with changing speeds, acceleration and
turnaround complications.
I didn't even mention mathematics. Physics is what copes with changing
speed/turnarounds/acceleration.
Post by Ed LakeWhen discussing REALITY, changing speeds,
acceleration and turnarounds just mean that the amount of time dilation will
vary during all those factors. That makes it difficult to do the math, but it
is what happens in REALITY.
REALITY can be predicted with the correct physics formulas. But solving
those formulas will mean doing the math. The whole purpose of physics is
to find and create accurate models of what nature is doing, to MATCH
reality, but those models often have loads of math. Since you appear to
be frightened of math, physics may not be for you.
Post by Ed LakePost by VolneyWhen the two clocks are together again, the clock that
was moved will show less time has passed than the clock that wasn't moved.
More accurately, the clock with the shorter path through spacetime
experiences more time.
More accurately, the clock that moved at the greater percentage of the speed
of light will show that less time has passed than the clock that moved
at the lower percentage of the speed of light.
That makes no sense, since there are three (or more) velocities
involved, and any one of them can be chosen to be 0 if the correct frame
is chosen.
Post by Ed LakePost by VolneyThe clock that moved will show less ELAPSED time has passed.
Because it took a longer path through spacetime. But this is the twins
gedanken, not simple relative motion.
That depends upon your definition of "simple relative motion."
Not my definition, Einstein's. Or Galileo's. It means inertial motion
with no acceleration. It means the two can meet each other at most
once, since there is no return. Time comparison is done with a signal
of some sort. Consider a distant galaxy moving away and we're
monitoring a sodium line. The remote sodium is both a clock (sends
light with a constant known frequency at the source) and the signal source.
Post by Ed LakePost by VolneyThe clock that
didn't move will still show the "proper time."
Its own proper time, not "the" proper time. The moving clock shows
*its* own proper time.
Post by VolneyPost by Ed LakeHowever, it is also true that, in terms of the momentarily co-moving inertial reference system of each object, we always have dtau/dt = 1, regardless of the object's state of motion or elevation. This is an expression of the principle of relativity (for the motion part) and the principle of equivalence (for the gravitational part). This is the empirically verified scientific fact that you (Ed) deny, but all the experiments on your list are perfectly consistent with this fact. So, again, your list is pointless. It merely confirms what every competent physicist has told you.
I don't deny things that are meaningless to me. Your mumbo-jumbo comment
is meaningless to me. "Momentarily co-moving inertial reference system"? Who
said anything about anything "co-moving" OR "momentarily co-moving"???
"Co-moving" with X simply means stationary as far as X is concerned
(zero velocity in X's reference frame). A second observer will see them
moving together, side by side, which is where the word "co-moving" comes
from!
"Momentarily co-moving" implies acceleration or something involved. It
means that for an instant of time ("momentarily"), X sees the object as
momentarily stationary. Think of a ball thrown straight up. It is
moving away from the thrower at first (vertical distance z increasing),
but it is accelerating to earth due to gravity. At some instant, the
thrower sees the ball stop moving away from him (z=0) and then start
falling down back toward him (z decreasing). At that instant when the
ball stopped rising and started falling, it was momentarily co-moving
with the thrower (as someone in space would see them, rotating with
earth and moving with earth around the sun etc., moving together)
This is a standard description of mechanics. If these terms are
confusing to you (you call them mumbo-jumbo), you need to LEARN.
Your mumbo jumbo
Not my mumbo jumbo, it is what's in every book on physical mechanics.
And it's physics, not "mumbo jumbo". As I said, if physics is mumbo
jumbo to you, you need to LEARN.
I'm not interested in learning mumbo jumbo.
Then physics isn't for you, if high school physics is mumbo jumbo to
you. May I suggest basket weaving as a hobby, instead?
Post by Ed LakeI'm just interesting in
learning how the universe works IN REALITY, not in mathematical models.
You are calling PHYSICS models "mumbo jumbo". If you think physics is
mumbo jumbo, you won't be able to learn how "the universe works in reality".
Post by Ed LakeYou have one mathematical model to explain light when it seems to travel
as a wave, and you have a different mathematical model to explain light
when it seems to travel as a particle. THAT IS STUPID!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
You may think it's stupid, but that was found through experiment.
There are some properties of light which cannot be explained by the wave
model, and other properties which cannot be explained by the photon
model. Again, that was found by experiment. Like it or not, light has
properties of both.
Post by Ed LakeIN REALITY, light is a particle that has oscillating electric and magnetic
fields which give it some wave-like properties.
You mean oscillating magnetic and electric field can be modeled as
particles sometimes.
Post by Ed LakeThe fact that mathematicians
WHAT mathematicians?
Post by Ed Lakecannot cope with that is why I look at REALITY, not just at the mathematics.
Your opinion that light is oscillating particles is just your opinion,
and just doesn't work for many physics situations.
Post by Ed LakePost by Volneyjust makes things confusing to YOU by adding in
unnecessary complications.
I have added nothing. Nature already has those "complications". It's all
in books on relativity, and is college freshman mechanics. I'm not
confused, you are. You even admitted freshman mechanics is "mumbo jumbo"
to you.
Right. I'm trying to separate the REALITY of Relativity from the mumbo jumbo
of Quantum Mechanics
Hey, you are the one who says light is photons only, that IS quantum
mechanics! Don't like QM, don't bring up photons. However for most
mechanical relativity type discussions, QM doesn't really matter.
Post by Ed Lakein order to understand how the universe works IN REALITY.
Physics is all about creating models, models which represent reality as
accurately as possible. If our models are correct, we can accurately
predict what the universe works.