MacM's Closure to a Length Contraction Thread

[MacM]

Originally Posted by Ken G

It is you who are incorrect. The second statement above is correct, what is incorrect is any suggestion that there is a problem here. There is none. As I said before, the error in your analysis is a failure to account for differences in synchronization of the clocks. This is often the mistake made by people who don't understand special relativity. I will explain.

Unfortunately you fail to realize that the way this gedanken has been formulated synchronization is not required. The issues is gamma functions due to relative veloicty and they occur without synchronization.

The only thing that must be done is to demonstrate that the accumulation of 18,000 ticks is done in the same 36,000 seocndsaccording to clock Am.

That is done by computing the interval between the informational Start/Stop signals. One way Gamma is verified. In absence of simultaneity (an illusion of motion) the reciprocity gamma is falisified.

[worzel]

Originally Posted by MacM

That is I contend that the correct test is to insure a common standard "t". In this case the "Am " clock is used for all data.

Then you are only considering what happens in A's frame, and indeed in that frame B and C really are dilated. Do the same from B's or C's frame and you'll find that actually it was the other two who's clocks were really dilated.

My bottom line contention is that Relativity of Simultaneity is not a bonafide time dilation affect. It is a measurement illusion affect due to relative motion and does not affect the accumulated time on clocks when subsequently compared in a common frame.

If both B and C turned around and returned to A would you agree that their clocks would have less elapsed time than A's?

Would you agree that both B's and C's clocks would agree if they performed symmetrical flight paths to return?

Would you agree that the amount by which B's and C's clocks would lag behind A's once they'd returned would be dependant on how long they travelled out and back inertially?

[MacM]

Originally Posted by worzel

Then you are only considering what happens in A's frame, and indeed in that frame B and C really are dilated. Do the same from B's or C's frame and you'll find that actually it was the other two who's clocks were really dilated.

You are almost there. What you fail to recognize is that the A/B and A/C dilated accumulated time is incompatable with the B/C C/B frame unless you include simultaneity which is an illusion of motion and not a change in gamma.

You distort your test by changing the standard to produce the appearance of consistancy but in reality there is no consistancy and it is impossible to produce data supporting that view of time dilation.

If both B and C turned around and returned to A would you agree that their clocks would have less elapsed time than A's?

Yes.

Would you agree that both B's and C's clocks would agree if they performed symmetrical flight paths to return?

Yes. But the gedanken eliminates the requirement to make such turn around and include the confusion of GR and simultaneity affects.

Would you agree that the amount by which B's and C's clocks would lag behind A's once they'd returned would be dependant on how long they travelled out and back inertially?

Yes. But again the gedanken makes it unnecessary for the round trip to be timed. The one way Gamma is demonstrated valid and the recipocal gamma claim is demonstrated impossible.

[worzel]

Originally Posted by MacM

You are almost there.

Why thank you

What you fail to recognize is that the A/B and A/C dilated accumulated time is incompatable with the B/C C/B frame unless you include simultaneity which is an illusion of motion and not a change in gamma.

For a start, there is a frame in which A is at rest, a frame in which B is at rest, and a frame in which C is at rest. I don't know what you mean by the B/C C/B frame. In each of the three frames of interest the plane (or whatever it's called) of simultaniety is different because they are moving relative to each other. Your refutation of this seems to depend on the assertion that the relativity of simultaneity is just an illusion. You haven't demonstrated how inconsistencies arise from it. Your thought experiment only has a hint of inconsistencey because you try to sum up all points of view from one - which you just can't do is SR. The reality of the situation in every day notions of distance and time are relative to the observer.

You distort your test by changing the standard to produce the appearance of consistancy but in reality there is no consistancy and it is impossible to produce data supporting that view of time dilation.

So you claim. But can you actually derive an inconsistency from SR?

But the gedanken eliminates the requirement to make such turn around and include the confusion of GR and simultaneity affects.

You don't need GR to figure out the twin paradox. And the relativity of simultaneity is right there in SR (and at the heart of the twin paradox). Your thought experiment has only demonstrated that your requirement of an absolute sense in which spatially separated and relativy moving clocks can be reckoned is inconsistent with SR, not that SR is itself inconsistent.

Yes. But again the gedanken makes it unnecessary for the round trip to be timed. The one way Gamma is demonstrated valid and the recipocal gamma claim is demonstrated impossible.

You'd better go into more detial, because I don't think anyone else can see how you've demonstrated anything of the sort.

The important thing about you agreeing with the twin paradox (where your B and C turn around) is that you agree that this effect is the same for both even though A is arbitrary, so you can't believe in any sort of absolute frame of reference afterall. And you agree that the amount by which A's and B's clocks differ on return can be lengthened simply by altering the interial parts of their flight - so you must agree that our arbitrarily (but inertially) floating A attributes their loss of time purely down to time dilation due to relative motion (in both directions). Of course, if A were to head off after B and B were to carry on inertially then B would account for A's lost time identically when A caught up with B, so the time dilation while A and B are separating must be equally real for both of them.

[MacM]

Originally Posted by Worzel

Why thank you

Glad to see you have a sense of humor.

For a start, there is a frame in which A is at rest, a frame in which B is at rest, and a frame in which C is at rest. I don't know what you mean by the B/C C/B frame.

Agreed I used a very loose meaning. I should have been more precise. B/C or C/B is not a frame but C as viewed from the B frame and B as viewed from the C frame.

Your refutation of this seems to depend on the assertion that the relativity of simultaneity is just an illusion.

Not correct. It is an illusion of measurement. Meaning it has not changed the amount of time at the local level. Only physical time dilation changes the accumulated time upon direct comparison of clocks in a common frame.

What one sees in remote viewing while in motion is "Perception" not the physical reality locally. Only when clocks are reunited in a common frame and display different accumulated times can one claim time dilation as physical reality. Now certainly one can compensate the "Perception" measurement being made while in motion at a distance and determine the tick rate and accumulated time differance if they know all the travel specifics.

But "What you see" IS NOT "What you get".

You haven't demonstrated how inconsistencies arise from it. Your thought experiment only has a hint of inconsistencey because you try to sum up all points of view from one - which you just can't do is SR. The reality of the situation in every day notions of distance and time are relative to the observer.

I agree that relatvisits object to stringent physics and want to dabble, or double dip, by changing measurement standards and making claims that on close inspection cannot be supported physically.

So you claim. But can you actually derive an inconsistency from SR?

I have but only if you acknowledge that Relativity of Simultaneity does not contribute to the ultimate accumulation of time differance upon direct comparison of two clocks in a common frame. That true change in time must be recorded as a differance by the clocks and not as a function of measurment while moving. That is the Twins age can only be considered at the time of being reunited.

You don't need GR to figure out the twin paradox. And the relativity of simultaneity is right there in SR (and at the heart of the twin paradox). Your thought experiment has only demonstrated that your requirement of an absolute sense in which spatially separated and relativy moving clocks can be reckoned is inconsistent with SR, not that SR is itself inconsistent.

Again. SR is made consistant if you allow alteration of your measurement standard by introducing simultaneity. But that goes beyond the gamma function and the claim mathematically that t' = t / (1 - v^2/c^2)^1/2.

Just where do you see simultaneity in the above time dilation formula? You don't. The claim in SR is that time is based on relative velocity period. It says nothing here about allowing clocks to run for different periods based on perception while in motion at some distance.

You'd better go into more detial, because I don't think anyone else can see how you've demonstrated anything of the sort.

The gedanken ONLY evaluates the time dilation function above. That is the affect on clocks based on some set period of relative inertial motion. Accumulated time by a clock is directly linked to its tick rate times the period of test.

Time dilation cannot be assessed nor recorded if the test period is not precisely the same as is done using Am as a master control clock.

The important thing about you agreeing with the twin paradox (where your B and C turn around) is that you agree that this effect is the same for both even though A is arbitrary, so you can't believe in any sort of absolute frame of reference afterall.

False. B and C are the only clocks which experienced F = ma. That is they are the clocks which have undergone some form of absolute change. A has made none and ALL emperical data will show that B and C have dilated equally inspite of having had relative velocity. Not vice-versa. That is an absolute function not a relative function which advocates but does not demonstrate reciprocity.

And you agree that the amount by which A's and B's clocks differ on return can be lengthened simply by altering the interial parts of their flight - so you must agree that our arbitrarily (but inertially) floating A attributes their loss of time purely down to time dilation due to relative motion (in both directions).

No I don't. And you cannot post any data which demonstrates that reciprocity exists.

Of course, if A were to head off after B and B were to carry on inertially then B would account for A's lost time identically when A caught up with B, so the time dilation while A and B are separating must be equally real for both of them.

False. You prove my point. Once A accelerates and joins B then they are now traveling at the same absolute velocity (what ever that might be).

[worzel]

Originally Posted by MacM

Agreed I used a very loose meaning. I should have been more precise. B/C or C/B is not a frame but C as viewed from the B frame and B as viewed from the C frame.

Well both of those correspond to B's rest frame and C's rest frame respectively, so that's clear now. So when you said "What you fail to recognize is that the A/B and A/C dilated accumulated time is incompatable with the B/C C/B frame unless you include simultaneity which is an illusion of motion and not a change in gamma." you were right in that you must include the relativity of simultaneity to make these frames compatable with A's, but SR prescribes that anyway, so that doesn't show that SR is inconsistent.

Originally Posted by MacM

Not correct. It is an illusion of measurement. Meaning it has not changed the amount of time at the local level. Only physical time dilation changes the accumulated time upon direct comparison of clocks in a common frame.

What one sees in remote viewing while in motion is "Perception" not the physical reality locally. Only when clocks are reunited in a common frame and display different accumulated times can one claim time dilation as physical reality. Now certainly one can compensate the "Perception" measurement being made while in motion at a distance and determine the tick rate and accumulated time differance if they know all the travel specifics.

Well I agree that a second in one's rest frame is a second, period. If you want to define time dilation such that it is only real when it is apparent by clock comparisons in a common frame then fine, that still doesn't show any inconsistency in SR, because SR just tells you how to transform events from one frame to another such that they remain consistent. The philosophy is left for mathematical ignoramuses like myself to argue over on an Internet BB

Originally Posted by MacM

I agree that relatvisits object to stringent physics and want to dabble, or double dip, by changing measurement standards and making claims that on close inspection cannot be supported physically.

If one must transform events such that intervals of time and space are no longer absolute according to the theory then the only possible objections are that it doesn't predict accurately or that it is inconsistent. Both of those objectiosn are incorrect for SR. Vague accusations of double standards because you just don't like the idea of time and space no longer being absolute is no more an objection than mine to Newton's theory because I just "know" that cannon balls fall faster than feathers.

Originally Posted by MacM

I have but only if you acknowledge that Relativity of Simultaneity does not contribute to the ultimate accumulation of time differance upon direct comparison of two clocks in a common frame. That true change in time must be recorded as a differance by the clocks and not as a function of measurment while moving. That is the Twins age can only be considered at the time of being reunited.

But it can be understood in terms of the relativity of simultaneity using SR. In the part I've bolded you are effectively saying that you have shown an inconsistency, but only if we accept your assertion that the relativity of simultaneity doesn't play a part in the differing times elapsed for the reunited twins. That is circular as we claim that it does play a crucial part.

Originally Posted by MacM

Again. SR is made consistant if you allow alteration of your measurement standard by introducing simultaneity. But that goes beyond the gamma function and the claim mathematically that t' = t / (1 - v^2/c^2)^1/2.

Just where do you see simultaneity in the above time dilation formula? You don't. The claim in SR is that time is based on relative velocity period. It says nothing here about allowing clocks to run for different periods based on perception while in motion at some distance.

It is implicit in the Lorentz transformation. In the twins paradox the sudden Lorentz tranformation causes clocks in the direction of the change to literally leap forward by a factor proportional to their distance from the turning twin. This is one and the same as saying the what is now over their to the twin changes as he turns - or in other words, what are simultaneous events is relative and is changed by a Galilean boost (i.e. a sudden change of reference frame via a Lorentz transformation).

Originally Posted by MacM

The gedanken ONLY evaluates the time dilation function above. That is the affect on clocks based on some set period of relative inertial motion. Accumulated time by a clock is directly linked to its tick rate times the period of test.

Time dilation cannot be assessed nor recorded if the test period is not precisely the same as is done using Am as a master control clock.

Your claim is that SR is inconsistent. Where does SR say that time dilation can only be reckoned as you prescribe? If it doesn't then your assertions don't support your claim of inconsistency.

Originally Posted by MacM

False. B and C are the only clocks which experienced F = ma. That is they are the clocks which have undergone some form of absolute change. A has made none and ALL emperical data will show that B and C have dilated equally inspite of having had relative velocity. Not vice-versa. That is an absolute function not a relative function which advocates but does not demonstrate reciprocity.

No, you are wrong. The twin experiment can be set up so that there is no acceleration simply by having conveniently moving observers crossing each others paths and comparing clocks when right next to each other. The same result occurs with no clock experiencing any acceleration, according to SR anyway, so your objection doesn't support your claim that SR is inconsistent.

Originally Posted by MacM

No I don't. And you cannot post any data which demonstrates that reciprocity exists.

But you did:

Would you agree that the amount by which B's and C's clocks would lag behind A's once they'd returned would be dependant on how long they travelled out and back inertially?

Yes. But again the gedanken makes it unnecessary for the round trip to be timed.

The fact that you find it unnecessary for your gedanken doesn't change the fact that you agreed with it. But if you don't, no matter, SR does. So unless you can show that SR also doesn't then this doesn't constitute a contradiction within SR either.

Originally Posted by MacM

False. You prove my point. Once A accelerates and joins B then they are now traveling at the same absolute velocity (what ever that might be).

You missed the point, which is forgivable because I'm not very good at making them. As I said above, the whole thing can be done with no acceleration anyway. The symmetry of the twin paradox is broken by the change of reference frame of one twin versus the other. This can be done with exactly the same effect with conveniently intersecting worldlines of accurate clocks moving inertially throughout.

Imagine your two twins floating off away form each other. One turns around and rejoins the other (or passes a conveniently moving clock and quickly sets it time). That one has aged less. The older, inertial one saw the younger one's clock ticking slower the whole time he was heading away and coming back (after discounting signal propagation times) exactly in accordance with SR's time dilation due to relative motion. And it doesn't matter which one turns around, the time dilation of both the outward and inward trip account for the difference.

From the point of view of the one that turned around, the other's clock also runs slow throughout: there's the recipricacy you keep denying. But when he turns around the others clock suddenly leaps forward (ignoring the time taken to turn arond, and after discounting signal propagation times): there's the relativity of simultaneity you keep denying. And it leaps just the right amount for the two periods of dilation pluss the leap due to change of FoR to account for the same difference that the inertial twin gets from just time dilation alone. And that's all there in the Lorentz transformation alone.

That's how it works in SR. It is consistent, and that leaping of distant clocks is the relativity of simultaneity in action. And it only works if you take the time dilation they both "see" into account (after propagation etc.) and the change in what is now over there for the turning one into account. Or in short, it works consistently for any observer precisely because of time dilation due to relative motion and the relativity of simultaneity.

Now, MacM, where is the inconsistency?

[Tensor]

Originally Posted by MacM

Again. SR is made consistent if you allow alteration of your
measurement standard by introducing simultaneity. But that goes beyond
the gamma function and the claim mathematically that t' = t / (1 -
v^2/c^2)^1/2.

Just where do you see simultaneity in the above time dilation formula?
You don't. The claim in SR is that time is based on relative velocity
period. It says nothing here about allowing clocks to run for
different periods based on perception while in motion at some
distance.

Mac, have you read the1905 paper? Look at section 1. The derivation of gamma, in section
3, requires the definition of simultaneity Einstein uses in section 1. So, simultaneity is in the equation, through the definitions used to derive gamma. You can't simply toss or ignore the definition of simultaneity found in the paper. What you have shown, is that if you ignore the definition of simultaneity found in SR, SR doesn't work. Why would that be a suprise?

[MacM]

Originally Posted by Worzel

Well both of those correspond to B's rest frame and C's rest frame respectively, so that's clear now. So when you said "What you fail to recognize is that the A/B and A/C dilated accumulated time is incompatable with the B/C C/B frame unless you include simultaneity which is an illusion of motion and not a change in gamma." you were right in that you must include the relativity of simultaneity to make these frames compatable with A's, but SR prescribes that anyway, so that doesn't show that SR is inconsistent.

I'm glad we can agree on at least something. It is inconsistant with the arguement that time (gamma) is a function of relative velocity. That arguement requires additional mathematical manipulation which is beyond the gamma function and has nothing to do with time dilation. You must ignore the comparative tick rates and allow clocks to run for extended periods to make the numbers come out right.

What I am showing is that the concept of relative velocity is inconsistant with physical reality as supported by acceptable logic and emperical data.

Emperical data does not support the reciprocity arguement.

Well I agree that a second in one's rest frame is a second, period. If you want to define time dilation such that it is only real when it is apparent by clock comparisons in a common frame then fine, that still doesn't show any inconsistency in SR, because SR just tells you how to transform events from one frame to another such that they remain consistent. The philosophy is left for mathematical ignoramuses like myself to argue over on an Internet BB

It is no longer philosophy when emperical data does not support the reciprocity arguement. What emperical data is trying to tell you is that such transformation manipulation is incorrect physically even if mathematically it achieves an internal consistancy.

If one must transform events such that intervals of time and space are no longer absolute according to the theory then the only possible objections are that it doesn't predict accurately or that it is inconsistent. Both of those objectiosn are incorrect for SR.

We disagree. Emperical data does not support the transformation manipulation arguement for a relative velocity view. Emperical data is only consistant with some absolute view.

Vague accusations of double standards because you just don't like the idea of time and space no longer being absolute is no more an objection than mine to Newton's theory because I just "know" that cannon balls fall faster than feathers.

Failure of emperical data to support reciprocity after 100+ years of testing is not a vauge accusation and the issues is not a matter of "I know cannon balls, etc". It is a matter of I have never seen and challenge you to present any data which supports reciprocity of time dilation.

But it can be understood in terms of the relativity of simultaneity using SR. In the part I've bolded you are effectively saying that you have shown an inconsistency, but only if we accept your assertion that the relativity of simultaneity doesn't play a part in the differing times elapsed for the reunited twins. That is circular as we claim that it does play a crucial part.

Think. Relativity of simultaneity only applies to moving frames. It has no lasting recorded affect on any frame. It is not relevant to the gamma vs physical change in accumulated time due to relative velocity.

It is implicit in the Lorentz transformation. In the twins paradox the sudden Lorentz tranformation causes clocks in the direction of the change to literally leap forward by a factor proportional to their distance from the turning twin. This is one and the same as saying the what is now over their to the twin changes as he turns - or in other words, what are simultaneous events is relative and is changed by a Galilean boost (i.e. a sudden change of reference frame via a Lorentz transformation).

Agreed that is the affect of the transformation but that still has no bearing on the gamma function due to inertial relative velocity. GR is simply not part of this discussion.

Your claim is that SR is inconsistent. Where does SR say that time dilation can only be reckoned as you prescribe? If it doesn't then your assertions don't support your claim of inconsistency.

Look it up. Time dilation due to inertial relative velocity is mathematically t' = t / (1 - v^2/c^2)^1/2, nothing more. All the rest has to due with the consequence of GR turn arounds, etc. This thread and issue is ONLY about the failure of relative veloicty in accordance with the formula as it stands.

No, you are wrong. The twin experiment can be set up so that there is no acceleration simply by having conveniently moving observers crossing each others paths and comparing clocks when right next to each other. The same result occurs with no clock experiencing any acceleration, according to SR anyway, so your objection doesn't support your claim that SR is inconsistent.

Sorry but that is mathematically incomplete. The crossing of paths withouth acceleration is good for a Start or Stop but not both.

The fact that you find it unnecessary for your gedanken doesn't change the fact that you agreed with it. But if you don't, no matter, SR does. So unless you can show that SR also doesn't then this doesn't constitute a contradiction within SR either.

Sorry but SR predicts reciprocity of time dilation. Please post at least ONE case of emperical data demonstrating that affect.

You missed the point, which is forgivable because I'm not very good at making them. As I said above, the whole thing can be done with no acceleration anyway. The symmetry of the twin paradox is broken by the change of reference frame of one twin versus the other. This can be done with exactly the same effect with conveniently intersecting worldlines of accurate clocks moving inertially throughout.

As stated above I disagree and I await your demonstration of how you can do that.

Imagine your two twins floating off away form each other. One turns around and rejoins the other (or passes a conveniently moving clock and quickly sets it time). That one has aged less. The older, inertial one saw the younger one's clock ticking slower the whole time he was heading away and coming back (after discounting signal propagation times) exactly in accordance with SR's time dilation due to relative motion. And it doesn't matter which one turns around, the time dilation of both the outward and inward trip account for the difference.

I have no disagreement with this other than you conveniently made a GR turn around. And yes their ends up being a deficeit of time in the frame which accelerated away in the first instance.

That is the point the frame (Twin) which remained at rest does not support the reciprocity arguement for relative velocity of SR. Are you in disagreement with SR that both Twins have a common relative velocity throughout the test?

If not then where is the time dilation predicted by the Twin that accelerated away and returned, for his stay at home brother.? SR relative velocity says he should be younger than him.

Where is the data which shows that the earth bound clocks in the H&K atomic clock test accumulated less time than the airborne clocks. That according to SR is the right of the pilots that ran the test to expect.

From the point of view of the one that turned around, the other's clock also runs slow throughout: there's the recipricacy you keep denying.

I have not denied anything. I clearly stated that illusions of measurment due to motion which do not result in recorded time change by accumulated time on the clocks is not physical time dilation but merely a perception matter and are not at issue here.

But when he turns around the others clock suddenly leaps forward (ignoring the time taken to turn arond, and after discounting signal propagation times): there's the relativity of simultaneity you keep denying.

Please keep it factual. I have not denied simultaneity. I have said and still say that simultaneity is not relatied to the gamma function.

And it leaps just the right amount for the two periods of dilation pluss the leap due to change of FoR to account for the same difference that the inertial twin gets from just time dilation alone. And that's all there in the Lorentz transformation alone.

And what you get and have is a one way gamma function without reciprocity. SR says both frames are equal and each can be considered as at rest and the other has all motion; hence experiences the relavistic affects. It just is not so.

That's how it works in SR. It is consistent, and that leaping of distant clocks is the relativity of simultaneity in action. And it only works if you take the time dilation they both "see" into account (after propagation etc.) and the change in what is now over there for the turning one into account. Or in short, it works consistently for any observer precisely because of time dilation due to relative motion and the relativity of simultaneity.

False. It consistantly only results in a ONE way gamma function in defiance of the reciprocity which is both inherent and advocated by the theory.

Now, MacM, where is the inconsistency?

Stated clearly above.

[MacM]

Originally Posted by Tensor

Mac, have you read the1905 paper? Look at section 1. The derivation of gamma, in section
3, requires the definition of simultaneity Einstein uses in section 1. So, simultaneity is in the equation, through the definitions used to derive gamma. You can't simply toss or ignore the definition of simultaneity found in the paper. What you have shown, is that if you ignore the definition of simultaneity found in SR, SR doesn't work. Why would that be a suprise?

Unfortunately the simultaneity issue only affects clocks while in motion.

This thread and the issue of physical time dilation involves only the differential time between clocks which started off synchronized but then have undergone relative motion and are no longer synchronized.

The issue is that only one will show time dilation which violates the claim of reciprocity in the relative velocity view advocated by SR.

[Nereid]

Continuing with the 'there are only 3 clocks' line of questioning ...

Originally Posted by MacM

[snip]

What I am showing is that the concept of relative velocity is inconsistant with physical reality as supported by acceptable logic and emperical data.

Emperical data does not support the reciprocity arguement.

I'm lost - isn't this a Gedankenexperiment? And MacM declares there are ~9 clocks, when there are, in fact, only three?

Where is the "empirical" basis for this?

Further, without the equivalent of a 'videolink' between the three clocks, what basis can any claims of "physical reality" have?

It is no longer philosophy when emperical data does not support the reciprocity arguement. What emperical data is trying to tell you is that such transformation manipulation is incorrect physically even if mathematically it achieves an internal consistancy.

What "emperical data"?

We disagree. Emperical data does not support the transformation manipulation arguement for a relative velocity view. Emperical data is only consistant with some absolute view.

That may be so.

However, as the MacM presentation is a Gendankenexperiment, there is no "empirical data".

If we were to introduce empirical data, it would be of the form of the (our frame) observed half-life of muons (for example), as a function of their (observed) speed.

But, unless I have misunderstood, MacM does not wish to consider actual empirical data (=experimental results), for now.

Failure of emperical data to support reciprocity after 100+ years of testing is not a vauge accusation and the issues is not a matter of "I know cannon balls, etc". It is a matter of I have never seen and challenge you to present any data which supports reciprocity of time dilation.

It seems we keep coming back to this.

So, once more for my own view:

• experiments to test the MacM assertions cannot be conducted, with today's technology
• it may be possible to do such tests, but it is unlikely they will be able to be done within the lifetime of any BAUT member reading this post today
• these aspects of SR, while perhaps interesting, are very minor, in overall scheme of things
• SR has, in fact, been tested in the lab, in thousands (possibly millions) of experiments, and no inconsistency has been detected, to date
• this most certainly does not mean that, at some time in the future, an experiment will be done, with the results being clearly inconsistent with SR
• if any ATMer would like to propose such a test, then let's see it!

[worzel]

MacM:

You mention emperical data a lot but you have shown no data whatsoever to support your claim, and despite many requests you have not shown where one out of the hundreds of experiments that support SR are wrong in their interpretation of the data.

You claim that SR is inconsistent but you have shown no such inconsistency. You appeal to "acceptable logic", what's that? Do you understand what "internally consistent" means?

You keep saying "think", "look it up", etc. when clearly your knowledge of SR is lacking. Do you really think that none of us have ever thought about it before? Do you really think that most of us didn't start out thinking "this just can't be right".

You appeal to gamm but brush off the Lorentz transformation as a GR turn around. You are just plain wrong, MacM, gamma comes from the Lorentz transformation which is itself the heart and soul of SR. The Lorentz transformation prescribes time dilation, length contraction, and relativity of simultaneity, and it is purely SR.

The twins paradox can be done with no acceleration. Just take two ships that pass at t0, and a third that passes one at t1 and the other at t2.

But anyhow, GR is not required for acceleration anyway. A smooth turnaround can be approximated with many small Lorentz transformations. In the limit as the number of transformations approaches infinity and the size of the transformations approaches zero we end up with acceleration and equations that work out to be the equations for a pseudo gravity field due to the acceleration. The term "pseudo gravity field" may fool you into thinking this is GR, but believe it or not this is still pure SR: it is just calculus applied to SR over flat spacetime.

Originally Posted by MacM

That is the point the frame (Twin) which remained at rest does not support the reciprocity arguement for relative velocity of SR. Are you in disagreement with SR that both Twins have a common relative velocity throughout the test?

If not then where is the time dilation predicted by the Twin that accelerated away and returned, for his stay at home brother.? SR relative velocity says he should be younger than him.

You failed your comprehension test. I already explained that while the twins are moving inertially they both "see" the other's clock running slow, and that the asymmetry is due entirely to the Lorentz transformation which entails a leap forward of distant clocks.

When you make an argument and I reply with an explanation and you make the same bogus argument again after clearly not reading, or chosing to ignore, the explanation given I do wonder why anyone would bother arguing with you. Are you capable of rational discourse? Or is this conversation a complete waste of time?

[MacM]

Originally Posted by Nereid

Continuing with the 'there are only 3 clocks' line of questioning ...I'm lost - isn't this a Gedankenexperiment? And MacM declares there are ~9 clocks, when there are, in fact, only three?

Three primary clocks of interest, yes. The others are inserted to give the fullest view of all the relationships and to effect control based on the rest frame without needing to send synchronized start/stop signals.

It is interesting to note that these clocks will read these numbers regardless of the validity of SR or not. However, the validity of SR (One way gamma) is verified by the measurement of the interval between the start/stop informational signals.

Where is the "empirical" basis for this?

Any and ALL data ever generated. Such data only supports the primary gamma function. That is the accelerated frame emperically demonstrates the affect of time dilation. NEVER the rest frame which is the recipocal frame view advocated by SR.

The data therefore does not distinguish between the origin of such affect being relative velocity or absolute velocity. The absence of any reciprocity data in these millions of tests strongly suggests that it is the absolute view and not a relative velocity view which should be explored.

Further, without the equivalent of a 'videolink' between the three clocks, what basis can any claims of "physical reality" have?

Not so. The measured interval between the informational start/stop signals sent by the shuttles insures that the clocks data is consistant with the gamma formula. It is that data which reflects the physical impossibility of such a system.

However, as the MacM presentation is a Gendankenexperiment, there is no "empirical data".

True but please show where any of the data is inconsistant with the gamma predictions of SR.

If we were to introduce empirical data, it would be of the form of the (our frame) observed half-life of muons (for example), as a function of their (observed) speed.

And I would insist on equal consideration of the recent findings regarding the correct "v" term being the absolute motion to the CMB and not relative velocity to earth.

So, once more for my own view:

• experiments to test the MacM assertions cannot be conducted, with today's technology
• it may be possible to do such tests, but it is unlikely they will be able to be done within the lifetime of any BAUT member reading this post today
• these aspects of SR, while perhaps interesting, are very minor, in overall scheme of things
• SR has, in fact, been tested in the lab, in thousands (possibly millions) of experiments, and no inconsistency has been detected, to date
• this most certainly does not mean that, at some time in the future, an experiment will be done, with the results being clearly inconsistent with SR
• if any ATMer would like to propose such a test, then let's see it!

I agree on the unlikely event of some actual testing of this sort. However, it should not go unnoticed that SR and the reciprocity affect were introduced in SR by the very use of gedankens and reciprocity remains a gedanken issue in that it has never been observed, measured or demonstrated. All test you just referred to demonstrate a one way primary gamma affect.

Time dilation has (and I suggest can) only be measured as a change in accumulated time in the frame which has accelerated, never the frame which remained at rest. Reciprocity is not a supported or supportable concept.

[Tensor]

Originally Posted by MacM

Unfortunately the simultaneity issue only affects clocks while

snip.....

reciprocity in the relative velocity view advocated by SR.

Since what I was replying to has nothing to do with the above, I'll point out again:

In particular, I was responding to the claims that you made:

Originally Posted by MacM

Again. SR is made consistent if you allow alteration of your
measurement standard by introducing simultaneity.

You don't have to introduce it, it's in the definitions, and thus built into the derivation of gamma. Hence, your measurement is altered by simultaneity, any time you use gamma.

Originally Posted by MacM

But that goes beyond the gamma function and the claim mathematically that t' = t / (1 -v^2/c^2)^1/2.

Just where do you see simultaneity in the above time dilation formula?
You don't.

I was pointing out that simultaneity is part of the definitions that are used to derive gamma. You claimed simultaneity goes beyond the gamma function,it does no such thing, it's part of it. You also claim you didn't see it in the gamma equation. Which makes it obvious, you either haven't noticed or fully understood how gamma is derived within SR.

I'm tending to agree with Worzel here. It simply sounds like another case of dejamoo.

[Celestial Mechanic]

Celestial Mechanic's Angels--2006 (Part One)

Three accomplished spaceship pilots, Anne, Barbara, and Charlotte, are huddled in an office, looking expectantly at the speakerphone. Their boss, the ever-mysterious Celestial Mechanic, has never spoken to his "Angels" in person. All communication has been through this speakerphone, which finally chimes in with the sound of Celestial Mechanic's voice.

"Good morning! I hope you will be able to conduct another gendankenexperiment for me."

"It's been more than two years since you've called on us," said Anne.

"We were beginning to worry," said Barbara, "after all, the world is still full of people without any understanding of relativity."

"Or of how to properly set up a gendankenexperiment, which is why I have called you here today," the Celestial Mechanic explained. "A new poster to BAUT Forum has run a very poorly conceived gendankenexperiment. Just have a look at this thread we're in."

"What happened to BABB?" asked Charlotte.

"It has been merged in with a similar forum at Universe Today to become the Bad Astronomy -- Universe Today Forum, or BAUT Forum for short. It has been a very active two years since I last called on your skills.

"Here is the flight plan--as usual the three of you will fly out to the outskirts of the Solar System several light-weeks away where we can ignore gravity enough for our purposes. Anne will remain in the ship which will be stationary while Barbara and Charlotte will fly shuttles in opposite directions at our canonical velocity of 0.6c for a total of four hours by your ships' clocks. During the whole time of the experiment the three of you will be broadcasting your ships' clock ticks at one second intervals as part of a packet containing your name and the time of emission. You will record the receipt of each packet in a data file with each datum consisting of the recorder's name, the timestamp of receipt, the sender's name, and the timestamp sent by the sender.

Barbara and Charlotte will send each other a special signal when they reach their halting positions. They will stay halted, that is, motionless with respect to Anne, until receiving the other's special signal at which time they will return to Anne's location also at a velocity of 0.6c."

"Why are you having us return?", asked Barbara. "It's not part of MacM's experiment."

"No, but you would like to return home, wouldn't you?" We all laughed. "Besides, there are a few more things we can demonstrate by closing up this experiment and making it like the Twins Experiment.

"Good luck and godspeed!" concluded Celestial Mechanic.

To be continued...

[Celestial Mechanic]

Celestial Mechanic's Angels--2006 (Part Two)

Several weeks later our pilots, Anne, Barbara, and Charlotte, return to the office with their data.

"Good morning! I hope all went well," said Celestial Mechanic via the speakerphone.

"We have the data you asked us to collect," said Anne.

"Very good. Could you please present the data at hourly intervals, normalized so that all timestamps are 00:00 for the beginning of the experiment?"

After a bit of paper-shuffling the following results were posted for Anne:

Anne     Barbara
-----    -------
00:00    00:00
01:00    00:30
02:00    01:00
03:00    01:30
04:00    02:00
05:00    02:30
06:00    03:00
07:00    03:30
08:00    04:00
09:00    05:00
10:00    06:00
11:00    07:00
12:00    08:00
13:00    09:00
14:00    10:00
15:00    12:00
16:00    14:00

The timestamps received from Charlotte were identical to Barbara's and are omitted here. Now Barbara's data:

Barbara  Anne     Charlotte
-------  -----    ---------
00:00    00:00    00:00
01:00    00:30    00:15
02:00    01:00    00:30
03:00    01:30    00:45
04:00    02:00    01:00
05:00    03:00    01:30
06:00    04:00    02:00
07:00    05:00    02:30
08:00    06:00    03:00
09:00    07:00    03:30
10:00    08:00    04:00
11:00    10:00    06:00
12:00    12:00    08:00
13:00    14:00    10:00
14:00    16:00    14:00

Charlotte's data was identical to Barbara's data with the headings of Barbara and Charlotte transposed, so we will omit that table here.

"Anne, how would you analyze your data?" asked Celestial Mechanic.

"For the first eight hours I received redshifted timestamp data from Barbara and Charlotte at a rate of half my clock's rate. This is consistent with Barbara and Charlotte flying away at 0.6c. At this time I received both of their special signals. For the next six hours the data arrived at the same rate as my clock, consistent with Barbara and Charlotte being at rest with respect to me. Finally, for the last two hours I received blueshifted timestamps consistent with an approach velocity of 0.6c.

"During my 16 hours of recording I received 4 hours of timestamps during the first 8 hours, 6 hours of timestamps for the next 6 hours and 4 hours of timestamps for the last 2 hours of my proper time, for a total of 14 hours of timestamps received during 16 hours. When Barbara and Charlotte docked with the spaceship, their clocks were indeed found to be two hours behind, reflecting the fact that they had measured two fewer hours of proper time than mine."

"Anne, at what time in your frame of reference did Barbara and Charlotte arrive at their stopping points?"

"I infer that they arrived at these stopping points at 5:00. They travelled at 3/5 c for five hours of my time, for a total of 3 light-hours in my frame. It took light an additional 3 hours to make it to me at 8:00 where I recorded their special signals. I can also infer that they both received each other's signals at 11:00 my time and that it took until 14:00 in my time until their data blueshifted and informed me of their impending arrival."

"And what is the proper time interval for the flight from your location to a location 3 light-hours away at a time of 5 hours later?", asked Celestial Mechanic.

"sqrt(5*5-3*3) or 4 hours, precisely the time recorded on Barbara's and Charlotte's clocks."

"Very good!", exclaimed Celestial Mechanic.

To be continued...

[Celestial Mechanic]

Celestial Mechanic's Angels--2006 (Part Three)

"Barbara, how would you analyze the data you received from Anne?" asked Celestial Mechanic.

"For the first four hours I received redshifted timestamp data from Anne at a rate of half my clock's rate. This is consistent with Anne flying away at 0.6c. Or me flying away from Anne at 0.6c. At this time I sent my special signal. For the next six hours the data arrived at the same rate as my clock, consistent with Anne being at rest with respect to me. At this time I received Charlotte's signal and started back. For the last 4 hours I received blueshifted timestamps consistent with an approach velocity of 0.6c.

"During my 14 hours of recording I received 2 hours of timestamps during the first 4 hours, 6 hours of timestamps for the next 6 hours. I then received 8 hours of timestamps for the last 4 hours of my proper time, for a total of 16 hours of timestamps received during 14 hours. When Charlotte and I docked with the spaceship, our clocks were indeed found to be two hours behind, reflecting the fact that we had measured two fewer hours of proper time than Anne."

"And Charlotte, how would you analyze the data you received from Barbara?" asked Celestial Mechanic.

"For the first four hours I received redshifted timestamp data from Barbara at a rate of one-fourth my clock's rate. This is consistent with Barbara and I separating at 15/17 c, the velocity resulting from the relativistic velocity addition formula for two velocities both equal to 3/5 c. At this point I sent my signal to Barbara. For the next 6 hours the signals were redshifted to a rate one-half of my clock's rate. Finally I received Barbara's signal and started back. Signals from Barbara were now blueshifted at a data rate twice my clock's rate, and for the last hour they were blueshifted to a rate four times that of my clock.

"During my 14 hours of recording I received 1 hour of timestamps in 4 hours, 3 hours of timestamps in 6 hours, 6 hours of timestamps in 3 hours and finally 4 hours of timestamps in 1 hour for a total of 14 hours of timestamps received in 14 hours of my proper time.

"Tell me, did any of you notice your clocks running at different rates?"

"No, of course not", the three pilots replied.

"Did any of your clocks run slower or faster than normal?"

"Of course not," replied Charlotte. "But even so, how could we tell?"

"Indeed, there is no hope of measuring this without reference to someone else's time," Celestial Mechanic continued. "And this is going to mean measuring and interpreting Doppler-shifted data, the very data that MacM dismisses as an 'illusion'. Yes, maybe what we see isn't what we get, but it is the best that we have and we must make the most of it. Ignoring this data and replacing it uncalibrated clocks running at calculated rates is about as meaningful as Judge Ito's collection of hourglasses.


"But of course there is nothing wrong with any of the clocks on board the spaceships. Each one recorded its proper time faithfully. Anne's clock recorded 16 hours of proper time, Barbara's and Charlotte's recorded 14 hours of proper time. The difference in times is real. Congratulations for a job well done!"

[MacM]

Originally Posted by Tensor

You don't have to introduce it, it's in the definitions, and thus built into the derivation of gamma. Hence, your measurement is altered by simultaneity, any time you use gamma.

Let me cut to the bottom line. How gamma is derived really has no bearing on the folloiwng facts.

A physical change in time is ONLY real if it affects the accumulated time on a clock in a permanent manner. That is two clocks once synchronized and one clock is accelerated away and upon return to the same frame demonstrates less accumulated time.

Simultaneity (and doppler) are affects of motion only and make no permanent changes in clocks. They are perception and mathematical manipulations which only mask the inconsistancy advocated by the gamma formula being applied in a relative velocity manner where reciprocity is produced.

There simply has been NO emperical data to support such a view.

[MacM]

Originally Posted by Celestial Mechanic

Celestial Mechanic's Angels--2006 (Part Three)

"Barbara, how would you analyze the data you received from Anne?" asked Celestial Mechanic.

"For the first four hours I received redshifted timestamp data from Anne at a rate of half my clock's rate. This is consistent with Anne flying away at 0.6c. Or me flying away from Anne at 0.6c.

Error #1. for gamma = 2.000 (one half clock rate) v = 0.866c not 0.6c.

........ For the last 4 hours I received blueshifted timestamps consistent with an approach velocity of 0.6c.
..............

"For the first four hours I received redshifted timestamp data from Barbara at a rate of one-fourth my clock's rate. This is consistent with Barbara and I separating at 15/17 c,

Second error. 1/4 clock rate is 0.9375c or 15 / 16c.

the velocity resulting from the relativistic velocity addition formula for two velocities both equal to 3/5 c.

Error three. Velocity addition for 3/5 c (0.6c) equals 0.88235c not 0.9375c.

Congratulations for a job well done!"

Ditto. I hope you also have a sense of humor.

[clj4]

Originally Posted by MacM

Error #1. for gamma = 2.000 (one half clock rate) v = 0.866c not 0.6c.

You are not serious, are you? Do you understand Doppler? Obviously not.

Second error. 1/4 clock rate is 0.9375c or 15 / 16c.

ha,ha,ha

If you throw a boomerang it might come back and clock you in the head. (old kiwi proverb)

"Celestial Mechanic" will have a party with these "pearls"

[MacM]

Originally Posted by clj4

You are not serious, are you? Do you understand Doppler? Obviously not.



ha,ha,ha

"Celestial Mechanic" will have a party with these "pearls"

Before you laugh yourself to hard perhaps you should recall that I have specificallys stated this is about gamma or t' = t(1-v^2/c^2)^1/2.

Doppler and simultaneity are irrelevant in that they are measurement changes during motion but do not cause permanent change in the accumulated time of clocks.

The issue here is only physical time dilation as demonstrated by clocks in a common test period accumulating permanent different amounts of time upon comparison in a common frame.

Your comments are inapplicable to the issue, unless you are prepared and able to post relevant emperical data to support the reciprocity advocated by SR.

[clj4]

Originally Posted by MacM

Before you laugh yourself to hard perhaps you should recall that I have specificallys stated this is about gamma or t' = t(1-v^2/c^2)^1/2.

Doppler and simultaneity are irrelevant in that they are measurement changes during motion but do not cause permanent change in the accumulated time of clocks.

The issue here is only physical time dilation as demonstrated by clocks in a common test period accumulating permanent different amounts of time upon comparison in a common frame.

Your comments are inapplicable to the issue, unless you are prepared and able to post relevant emperical data to support the reciprocity advocated by SR.

One sentence (from CM's post) "Doppler red/blue shift"

Think about it.

It is great to get people like you out of arguing with words and making you write down a simple piece of arithmetic.

[Ken G]

Originally Posted by MacM

Unfortunately you fail to realize that the way this gedanken has been formulated synchronization is not required. The issues is gamma functions due to relative veloicty and they occur without synchronization.

Here goes one more time:

The space station will not agree that clock Bac is recording time in the same way as time elapses in the space station's frame, because it is not going to agree with the synchronized remote clocks in the space station's frame. In 36,000 space station seconds, shuttle B's clock ticks 18,000 times, and shuttle B concludes that the space station's clock has ticked 9,000 times but shuttle B thinks the local stationary clock showing 36,000 seconds is not properly synchronized with the space station clock. The space station does not agree, it thinks the clocks are perfectly synchronized. This completely resolves all of your objections, there is no remaining problem. Please point out any flaw in this argument, instead of just asserting that it doesn't have to do with synchronization, because it very much does.

[Tensor]

Originally Posted by MacM

Let me cut to the bottom line. How gamma is derived really has no bearing on the folloiwng facts.

snip...

Simultaneity (and doppler) are affects of motion only and make no permanent changes in clocks. They are perception and mathematical manipulations which only mask the inconsistancy advocated by the gamma formula being applied in a relative velocity manner where reciprocity is produced.

snip...

Hey, you're the one that claimed that simultaneity was not in the gamma equation. You're the one who said it went beyond gamma. All I was doing was showing you how. where, and why simultaneity is part of relativity, refuting your contentions.

So why make those claims if it doesn't matter? About the only reasons I can see are either you were trying to deliberately set up a strawman or you didn't understand relativity well enough to know that gamma includes simultaneity. Which one is it?

[MacM]

Originally Posted by clj4

One sentence (from CM's post) "Doppler red/blue shift"

Think about it.

It is great to get people like you out of arguing with words and making you write down a simple piece of arithmetic.

Red or Blue are both measurements as a result of motion and do not result in permanent measureable change. The measured change is simply a matter of the gamma formula over equal periods of recording.

[clj4]

Originally Posted by MacM

Red or Blue are both measurements as a result of motion and do not result in permanent measureable change. The measured change is simply a matter of the gamma formula over equal periods of recording.

What does the navy have to do with the price of the beef? Go to post #79.

[MacM]

Originally Posted by Ken G

Here goes one more time:

The space station will not agree that clock Bac is recording time in the same way as time elapses in the space station's frame, because it is not going to agree with the synchronized remote clocks in the space station's frame. In 36,000 space station seconds, shuttle B's clock ticks 18,000 times, and shuttle B concludes that the space station's clock has ticked 9,000 times but shuttle B thinks the local stationary clock showing 36,000 seconds is not properly synchronized with the space station clock. The space station does not agree, it thinks the clocks are perfectly synchronized. This completely resolves all of your objections, there is no remaining problem. Please point out any flaw in this argument, instead of just asserting that it doesn't have to do with synchronization, because it very much does.

Nowhere have I stated A sees B or B sees C, etc. This is a blind test and all that is being done is subsequent to the testing is comparing accumulated time on the clocks.

Synchronization is irrelevant to the test or its results. The only physics involved is to insure the interval between informational Start/Stop signals is 36,000 seconds according to clock Am to verify the gamma function and the accumulated times.

[MacM]

Originally Posted by Tensor

Hey, you're the one that claimed that simultaneity was not in the gamma equation. You're the one who said it went beyond gamma. All I was doing was showing you how. where, and why simultaneity is part of relativity, refuting your contentions.

So why make those claims if it doesn't matter? About the only reasons I can see are either you were trying to deliberately set up a strawman or you didn't understand relativity well enough to know that gamma includes simultaneity. Which one is it?

I think we are getting symantical here. I never said simultaneity was not part of relativity. I said it is not part of this test.

[clj4]

Originally Posted by MacM

Nowhere have I stated A sees B or B sees C, etc. This is a blind test and all that is being done is subsequent to the testing is comparing accumulated time on the clocks.

Synchronization is irrelevant to the test or its results. The only physics involved is to insure the interval between informational Start/Stop signals is 36,000 seconds according to clock Am to verify the gamma function and the accumulated times.

Go to post #79

[MacM]

Originally Posted by clj4

What does the navy have to do with the price of the beef? Go to post #79.

More to the point what possible connection do you make between your post and the fact that accumulated time on a clock is t' = t / gamma*. t' is strictly a function of t, not t1 or t2 or t3 as functions of simultaneity views due to motion of observers 1, 2, or 3 at differing velocities.

The only thing being tested is how many tick does each clock do during an equal test period. The equal test period is to mimic relative velocity.

Relative velocity must be simultaneous to be relative but the only attribute that affects comparative accumulated time on the clock is the equal physical duration of the test.

Red or Blue shift are features of measurement between frames "During Motion". This test is blind and the only thing being done is comparing clocks in a common frame subsequent to a common test period.

*where gamma = 1 / (1 - v^2/c^2)^1/2

[Celestial Mechanic]

"Pearls" indeed, clj4!

A quick review for MacM. For velocity v we have:

gamma(v) = 1/sqrt(1-v²/c²)

Doppler redshift in frequency for object moving away from observer at velocity v:

redshift(v) = gamma(v)*(1-v/c) = sqrt((1-v/c)/(1+v/c)).

For the velocities in your gedankenexperiment:
gamma(sqrt(3)/2)=2
redshift(sqrt(3)/2) = 2-sqrt(3)
gamma(4*sqrt(3)/7)=7
redshift(4*sqrt(3)/7) = 7-4*sqrt(3).

In my gedankenexperiment:
gamma(3/5)=4/5
redshift(3/5)=1/2
gamma(15/17)=8/17
redshift(15/17)=1/4.

If you cannot understand the calculation and meaning of the quantities above you should not be criticizing special relativity. Get thee to a library! And if you do, be sure to read a real textbook on special relativity, not some potboiler by Herbert Dingle.