MacM's Closure to a Length Contraction Thread

[Ken G]

Originally Posted by MacM

I have now read this:

http://home.netcom.com/~heensle/phys/twins.html

You would also do well to read this:

http://arxiv.org/PS_cache/physics/pdf/0512/0512196.pdf

The second is quite an interesting link, because it demonstrates the importance of the scheme used to synchronize clocks. That is kind of the "invisible" element of SR that people rarely make mention to, but it is crucial. The first link is a perfect example of this: it is the kind of garbage you come up with if you fail to recognize the significance of appropriate clock synchronizations.

[MacM]

Originally Posted by Nereid

Thanks.

But didn't you, in an earlier post^, caution us against making ad hoc, a priori assumptions? In this case, why assume that the motion of earthly labs is ~300 km/s? Couldn't it just as well be ~300 nm/s? or ~0.99999c?

No. Not a valid point. There have been over a hlf dozen different tests which measured the absolute motion to the CMB over more than a decade of time. The values ranged from 200+km/sec to 600km/sec. However most were in the general range of 300-360km/sec. The average is around 300 km/sec.

Also there are other experiments (several) which have measured a East/West deviation in communications by wire signals which also vary in a dinural manner.

So this is not a case of one cosmic test but is based on numerous such results.

Once you put some kind of number on the table (even if it's only an OOM, for back-of-the-envelope purposes), it becomes a whole lot easier to look at (historical) experiments and observations, for 'motion wrt an absolute frame' signals, n'est pas?

So how about this simplifying assumption: whatever the 'absolute frame' is, there will be a ~24 hour* periodic signal in any test data taken anywhere on the Earth's surface (except, perhaps, at the poles)? If you're OK with that, then all (!) we would need to do is do a Fourier transform on any dataset**, and look for a signal at ~24 hours (plus harmonics), right?

One advantage of this approach is that it is 'blind' to details of the 'absolute frame' - any ~24 hour (nearly) periodic signal would hint at such a frame, right?

^"You really shouldn't assume anything. That is what got you in trouble at the outset. No the CMB may not be at rest"
*It might, of course, be a ~12 hour signal, if it picked up only the amplitude.
**or equivalent; I'm not saying any one analytic technique is better than any other, just giving an example

I am open to looking at any data which can be quantified both as to repeatability and to specific orientation at the time of the test. If the tests are of sufficient sensativity then they should be useful at looking for such absolute affect.

[MacM]

Originally Posted by Ken G

The second is quite an interesting link, because it demonstrates the importance of the scheme used to synchronize clocks. That is kind of the "invisible" element of SR that people rarely make mention to, but it is crucial. The first link is a perfect example of this: it is the kind of garbage you come up with if you fail to recognize the significance of appropriate clock synchronizations.

I wouldn't get to excited about these specific examples. If I am able to proceed with my scenario I believe you will see that such synchronization issues are irrelevant in the long term assessment.

[Nereid]

Originally Posted by MacM

No. Not a valid point. There have been over a hlf dozen different tests which measured the absolute motion to the CMB over more than a decade of time. The values ranged from 200+km/sec to 600km/sec. However most were in the general range of 300-360km/sec. The average is around 300 km/sec.

Well, the good news is that, as this forum has lots of 'astronomy nuts' on it, all the observed motions wrt 'the CMB frame' are well understood, and well constrained (if you'd like a summary, just holler).

The bad news, for your 'absolute frame' idea, is that I think you'll have an immensely difficult time showing that any observations can establish any 'absolute frame' similar to that of the CMB (unless, of course, you leave the realm of 'in principle, testably different predictions'; re-writing SR/GR in a way that includes an 'absolute frame', but cannot - even in principle - yield any exerimentally/observationally based test to distinguish it from SR/GR may well be possible, but then you're no longer doing science, IMHO).

But that's a path that, now, lies clearly before us (later).

Also there are other experiments (several) which have measured a East/West deviation in communications by wire signals which also vary in a dinural manner.

Such as? Please provide only the ones that you feel are the strongest.

So this is not a case of one cosmic test but is based on numerous such results.

I am open to looking at any data which can be quantified both as to repeatability and to specific orientation at the time of the test. If the tests are of sufficient sensativity then they should be useful at looking for such absolute affect.

Let's start with the Michelson-Morley experiments, and all its later variations, independent validations, etc, shall we?

What is your claim wrt these (i.e. that this set of classes of experiments are inconsistent with an 'absolute frame' more or less the same as the CMB)?

[Nereid]

Originally Posted by MacM

I wouldn't get to excited about these specific examples. If I am able to proceed with my scenario I believe you will see that such synchronization issues are irrelevant in the long term assessment.

I'm afraid I've lost much of my interest in your claims MacM, unless you can show - in as specific and detailed a way to answer my questions - that your idea leads to in principle observably different predictions from SR/GR.

I mean, creating a new set of theories which have exactly the same obserables as SR/GR may be an interesting intellectual exercise, but if there's nothing I can do with my lab equipment and telescopes to test whether it's a 'better' explanation of the universe than SR/GR, why should I bother? (this is, for avoidance of doubt, a rhetorical question).

[Nereid]

Originally Posted by MacM

[snip]

Yes and if unfalisifiable then the theory does not meet the standard to be called theory. It is a hypotheses.

[snip]

I'm happy to discuss what constitutes science (and theories, and physics, etc), but not in this thread.

If you wish, I will start (yet another) thread in BAUT's General Science section on this topic.

In the meantime I merely note that your opinion differs significantly from my own, and that even Popper abandonded the 'naive falsificationism' view of what constitutes science, for reasons that include a very easy demonstration that such a view is easily falsified.

[MacM]

Originally Posted by Nereid

I'm afraid I've lost much of my interest in your claims MacM, unless you can show - in as specific and detailed a way to answer my questions - that your idea leads to in principle observably different predictions from SR/GR.

I mean, creating a new set of theories which have exactly the same obserables as SR/GR may be an interesting intellectual exercise, but if there's nothing I can do with my lab equipment and telescopes to test whether it's a 'better' explanation of the universe than SR/GR, why should I bother? (this is, for avoidance of doubt, a rhetorical question).

We seem to be getting a diversification here between where clj4, yourself and others are going.

I think (or at least I thought) I made the distinction between SR and my view rather clear. It should produce results nearly identical to current emperical data (the exception being this underlying minor deviation which would demonstrate the existance of absolute motion vs relative motion) as being correct physics.

The major differance, and I feel it is extremely important, is what it does not include and that is predictions of reciprocity of relavistic affects, spatial length contraction and v = c as a limit.

Eliminating those I think are signifigant differances worth exploring. How to do that seems to be where we are diversifying.

I am suggesting that one can come to some conclusions via the gendankin route. Having agreed on such results you then might find you have greater interest in researching existing data or performing specific new tests to confirm or falsify the view.

[Nereid]

Originally Posted by MacM

We seem to be getting a diversification here between where clj4, yourself and others are going.

I think (or at least I thought) I made the distinction between SR and my view rather clear. It should produce results nearly identical to current emperical data (the exception being this underlying minor deviation which would demonstrate the existance of absolute motion vs relative motion) as being correct physics.

The major differance, and I feel it is extremely important, is what it does not include and that is predictions of reciprocity of relavistic affects, spatial length contraction and v = c as a limit.

Eliminating those I think are signifigant differances worth exploring. How to do that seems to be where we are diversifying.

I am suggesting that one can come to some conclusions via the gendankin route. Having agreed on such results you then might find you have greater interest in researching existing data or performing specific new tests to confirm or falsify the view.

[moderator mode]
If you wish to continue with this gedanken route, then please make that very clear.

Please also make it clear that you are making no claims whatsoever about any experimental or observational support for a "CMB" (or similar) absolute frame (at least until your 'gedanken experiment' discussion has run its course).

If you'd like to do both, but want to keep them 'clean', then please start a separate thread on experimental/observational results which are (or are not) consistent with an 'absolute frame'.

Note that, under the ATM rules, if you make statements about experimental/observational results being consistent with an 'absolute frame' (or not - as you did in the OP), they can be challenged (and you will have to defend them); if you don't want these things to be part of your 'gedanken experiment', then make it clear they are outside the scope of your claims.
[moderator mode]

[MacM]

Originally Posted by Nereid

[moderator mode]
If you wish to continue with this gedanken route, then please make that very clear.

Please also make it clear that you are making no claims whatsoever about any experimental or observational support for a "CMB" (or similar) absolute frame (at least until your 'gedanken experiment' discussion has run its course).

If you'd like to do both, but want to keep them 'clean', then please start a separate thread on experimental/observational results which are (or are not) consistent with an 'absolute frame'.

Note that, under the ATM rules, if you make statements about experimental/observational results being consistent with an 'absolute frame' (or not - as you did in the OP), they can be challenged (and you will have to defend them); if you don't want these things to be part of your 'gedanken experiment', then make it clear they are outside the scope of your claims.
[moderator mode]

OK. Lets give it a try.

This is merely a gendankin to explore possible cracks in the shell that surrounds SR.

I take your response here to be a "Yes" as to the question posed above and will now ask the next question. These questions are establishing the foundation of agreement from which to evaluate the gendankin.

Since relavistic affects are formulated, they are calcuable.

Do you agree that if we assume SR valid we can apply its predictions in a useful manner to the gendankin so as to have synchronized control.?

(This is not meant to claim synchronizing of relativity of simulataniety but to render it moot)

[Ken G]

What do you mean by synchronized control? Also, can you summarize again the gedankin you mean, and the possible interpretations you are giving? Note that it is always possible to come up with equivalent interpretations that don't agree with the standard interpretation, and it is interesting to do so, but does not constitute a new theory.

[Grey]

Originally Posted by Nereid

It has passed all such test to date, with flying colours. (The only apparent exception that I know of is the muon thing which you referenced in another thread).

You are claiming that no test to date (other than, perhaps, the muon one) has examined some 'absolute frame' idea which you have.

And as I pointed out in the first thread where this was mentioned, the error range in the data is rather too large to be able to observe the effects MacM and the authors of that paper are asserting. The authors acknowledge the large error range, too.

[MacM]

Originally Posted by Ken G

What do you mean by synchronized control? Also, can you summarize again the gedankin you mean, and the possible interpretations you are giving? Note that it is always possible to come up with equivalent interpretations that don't agree with the standard interpretation, and it is interesting to do so, but does not constitute a new theory.

The gendankin has not yet been described. I was trying to reach a concensus on what is agreed before posting it.

Sybnchronized in this context simply means that the affects can be accounted for and compensated for in the gendankin.

[MacM]

Originally Posted by Grey

And as I pointed out in the first thread where this was mentioned, the error range in the data is rather too large to be able to observe the effects MacM and the authors of that paper are asserting. The authors acknowledge the large error range, too.

Agreed. Nor would I claim it as a proof but only that it is extremely interesting and merits further consideration.

[MacM]

Since no specific objection has been raised to the question I'll move on to the last question before posting the gendankin.

Do you agree that the only time dilation which can be considered an actual change in time is that which becomes recorded by accumulation of time on a clock when compared in the same frame as the rest clock?

That is certain illusions of perception due to motion of the observer do not constitute actual change in time. To be a change in time then the twin must physically be younger when compared back together.

[Grey]

Why don't you just describe what you're actually imagining? Your question is a little strange. I'd still consider it time dilation if I measure a different clock moving at a different rate, but I'd certainly agree that it's a more dramatic result if I can bring two originally synchronized clocks back together and show that they are no longer synchronized. By the way, it's a "gedanken" experiment, from the German word for "thought".

[Disinfo Agent]

It's Gedankenexperiment in German, for pedants, and "thought experiment" in plain English.

[Ken G]

Originally Posted by MacM

Do you agree that the only time dilation which can be considered an actual change in time is that which becomes recorded by accumulation of time on a clock when compared in the same frame as the rest clock?

This one might cause problems, depending on what you mean by "in the same frame". I agree there is a big difference between what two clocks say when you compare them side by side, and what they appear to say when you look at them from different distances. But it is also important to recognize that the latter brings in two completely separate issues, the first is illusions due to time of flight effects, and the second is actual relativity, which is what you get after correcting for time of flight effects. So what I'm saying is, it is valid to observe the passing of time in a distant system, so long as you correct for the time of flight effects, but then you will still find time dilation as a leftover effect. We should not rule out this type of "observation", lest we rule out all of astronomy as a branch of physical observations.

[MacM]

Originally Posted by Grey

Why don't you just describe what you're actually imagining? Your question is a little strange. I'd still consider it time dilation if I measure a different clock moving at a different rate, but I'd certainly agree that it's a more dramatic result if I can bring two originally synchronized clocks back together and show that they are no longer synchronized. By the way, it's a "gedanken" experiment, from the German word for "thought".

Bear with me I started writting it last night but had to take one of our grandsons to the hospital for a shot due to high fever. I'll be working on it this week end.

[MacM]

Time Dilation (Spatial Length Contraction) Gendanken:

************************************************** ***
This gendanken is to test the assertions made by the relative velocity view of Special Relativity.

It takes place in deep space away from any large masses and involves only timing during inertial conditions such that GR affects can be ignored. (Hint do not regurgitate the "Twins" arguement).

The space station shall be labled "A". Two shuttle craft on board are labled "B" and "C". The scientist aboard are planning a mission to test SR and are aware of complexities of testing which would involve Relativity of Simultaneity and so they opt to lay out a flight schedule where only inertial relative velocity to the space station will be timed.

Acceleration/deceleration and simultaneity issues are circumvented making it possible to consider only the predictions regarding relative velocity and time dilation hence indirectly length contraction.

They decide to launch the shuttles in opposite directions simultaneously with equal acceleration for the same period of time according to a master clock in the space station, such that they each achieve a relative velocity of 0.866c to the station. That makes gamma = 2.000 and means each shuttle clock must tick at the rate of one tick for each two ticks of the master clock aboard the station.

The flight schedule is precalculated such that when mathematically the shuttles have reached their target velocity they begin to coast and become inertial and at that time the clocks aboard the shuttles and the space station all begin to record time. Both shuttles transmit a start information signal to the space station.

One can argue about this being simultaneous or not but it doesn't affect the conclusions of the test and can be ignored.

The point is all clocks are recording time at their proper rate while in an inertial (rest) state. The space station and each shuttle is equipped with several clocks.

The capital letter designates in which frame the clock is mounted, followed by "m" means it is the master clock ticking at the proper time rate for that frame. Followed by "a", "b" or "c" means it has been calibrated to reflect the time of the master clock of the frame designated by the small letter. Followed by a "p" means the time is what is predicted by relativity for observers of the frame designated by the capital letter or followed by a "c" means it is calibrated to tick in synch with clock Am for control purposes.

All of these calibrations can be made via precalculation of Special Relativity predictions.

Since the time dilation is precalculated based on the planned flight schedule it is known that (assuming Special Relativity is valid) the proper shuttle clocks, Bm and Cm, will be ticking at one half the rate of Am. Control monitoring clocks have been precalibrated and installed in each shuttle to run at two ticks per each tick of clocks Bm and Cm. They are labled Bac and Cac.

The space stations shuttle prediction monitoring clocks are labled Abp and Acp and are calibrated to tick at one half the rate of Am so as to allow the station operators to know what time has accumulated aboard the shuttles.

The monitors Bac and Cac allow the pilots of the shuttles to see and operate in accordance with the rate that time is passing back at the space station clock Am.

Due to Velocity Addition the relative velocity between "B" and "C" is 0.9897c and Gamma is 6.984 and their clocks each tick at the rate of only 143 ticks per 1,000 ticks of the other.

Respective prediction clocks have been precalibrated in B and C so as to accumulate time of the other as predicted by Special Relativity. That is the clocks will only record 143 ticks for each 1,000 ticks of the respective local proper time clocks Bm and Cm are labled Bcp and Cbp.

The flight schedule is set to be 10 hours inertial testing from the Am clock.

So that after 36,000 ticks (seconds) according to Am and according to Bac and Cac all clocks stop. Each shuttle transmits a stop information signal back to the space station.

Again the simultaneity of these actions can be argued but have no bearing on the issue at hand and can be ignored.

The results of this test are as follows:

Am = 36,000 Abp = 18,000 Acp = 18,000

Bac = 36,000 and stops all B clocks.
Cac = 36,000 and stops all C clocks.

Bm = 18,000 Cm = 18,000

Bap = 9,000 Cap = 9,000

Bcp = 2,574 Cbp = 2,574

Put into a more understandable configuration where predicted accumulated times of clocks A, B and C are more obvious:


Clock A
------------
Am = 36,000 Test master clock reading.
Bac = 36,000 Shuttle B test control clock.
Cac = 36,000 Shuttle C test control clock.
Bap = 9,000 Shuttle B's incorrect prediction of Am time.
Cap = 9,000 Shuttle C's incorrect prediction of Am time.

Clock B
-------------
Bm = 18,000 Shuttle B master proper time clock test reading.
Abp = 18,000 Station A's correct prediction for Bm test reading.
Cbp = 2,574 Shuttle C's incorrect prediction of Bm test reading.


Clock C
-------------
Cm = 18,000 Shuttle C master proper time clock test reading.
Acp = 18,000 Station A's correct prediction for Cm test reading.
Bcp = 2,574 Shuttle B's incorrect prediction of Cm test reading.


SUMMARY:

Before others point this out let me acknowledge that you are going to be inclined to claim that this test is not testing the affect of motion on clocks in that I am controlling the clocks with precalibrated timers so as to stop at preselected accumulated times per Special Relativity predictions.

But don't throw up your hands yet. There is some interesting things that can infact be demonstrated here.

1 - Accumulated times based on tick rates predicted by Special Relativity due to only relative motion do not agree with times actually accumulated in the test.

2 - The assumption that Special Relativity is valid results in evidence which shows that the theory requires physical clocks to accumulate time at multiple rates so as to satisfy predictions of multiple observers having different relative velocities. A physical impossibility.

3 - The fact that these times are based on actual affects of motion is verfiable in that the start/stop information signals sent from the shuttles can be used to determine that infact the test period was 36,000 seconds according to the master clock Am.

That is all data is based on the same universal time period to a common standard. In that regard the issue of simultaneity which is generally used to mask such comparisons is rendered moot.

In this manner IF the affect of motion were not as per SR then the clock readings would still be the same BUT start/stop signals differentail duration from the shuttles would not be 36,000 seconds according to the master control clock Am.

4 - Special Relativity requires that clocks B and C both tick at a rate of 0.5 / 1 to the space station clock. That is B and C are ticking at a common rate inspite of the fact that they have a relative velocity to each other which also requires them to tick at rates of about 1 tick to 7 ticks of the other. Impossible reciprocity and impossible ticking conditions for all views.

Note Added: lables for test results in red. It should be noted that it is reciprocity predictions which fail, not the primary gamma calculations.