I SR Time Dilation in Rigid Structure Clocks

[meopemuk]

For a different take on the moving clock problem you can check these articles are references therein:

1. B. T. Shields, M. C. Morris, M. R. Ware, Q. Su, E. V. Stefanovich, R. Grobe, "Time dilation in relativistic two-particle interactions", Phys. Rev. A, 82 (2010) 052116
2. E. V. Stefanovich "Moving unstable particles and special relativity" Adv. High Energy Phys., 2018 (2018) 4657079.

Eugene.

 

[Malvia]

You may be able to extend your point to length measurement also. Materials of measures, e.g. steel wood with condition of temperature, pressure etc. could be investigated to make them work in coordinated ways. Laser beam measurement could be added.
Same way of coordination will be applicable in all the IFRs. This is a principle of SR.

I am not sure that the same argument can be raised for Length contraction, because there is no L "formula" of an object, whereas we have a T formula for a clock. So you cannot say the L in the other frame must match values of some other quantities in that frame.

 

[sweet springs]

Well, in addition to what I said in #30 for length measurement, there are many ways in measuring time, e.g. water clock, sand clock, pendulum clock, atomic clock, light clock, GPS, etc. All these measuring methods should be coordinated and adjusted to show same time in one IFR. For an example, atomic clock and pendulum clock both at rest in IFR A should be adjusted in a manner. We can expect in another IFR B the same manner would be applied to atomic clock and pendulum clock both at rest in IFR B. ( At rest I say means "as a whole" , e.g. pendulum of clock goes to and fro and not at rest in any IFR.)

 

[Orodruin]

water clock, sand clock, pendulum clock

All of which are examples of clocks that do not work properly in an inertial frame (see #12) as they are utterly dependent on the external gravitational field.

 

[Dale]

there is no L "formula" of an object

Well, there is but you just don’t come to it until you start studying condensed matter physics. In any case, you would have to use the relativistic law, not the low speed approximation.

 

[Malvia]

Note that for atomic clocks (moving electrons), light clock (moving photons), muons there is an inner mechanism where motion of inner particles is causing the T of these clocks, so there is an intuitive sense in T formula being affected. But in a rigid structure clock such as a tuning fork clock, do we not have a paradox of sorts?

Looking at the experimental status it would seem that Special Relativity Time Dilation verification has so far been done only for muons and atomic clocks, and not for rigid structure clocks. I suppose this is because rigid structure clocks do not have the accuracy to show time dilation, at currently available speeds.

 

[Malvia]

Well, there is but you just don’t come to it until you start studying condensed matter physics. In any case, you would have to use the relativistic law, not the low speed approximation.

Would you kindly provide references? Thanks.

 

[Dale]

Looking at the experimental status it would seem that Special Relativity Time Dilation verification has so far been done only for muons and atomic clocks, and not for rigid structure clocks. I suppose this is because rigid structure clocks do not have the accuracy to show time dilation, at currently available speeds.

Well, it is far more than muons and atomic clocks, but yes nobody has accelerated a tuning fork to near c and measured the pitch. Time dilation has been confirmed for the EM force, weak force, strong force, and gravity.

 

[Herman Trivilino]

Looking at the experimental status it would seem that Special Relativity Time Dilation verification has so far been done only for muons and atomic clocks, and not for rigid structure clocks. I suppose this is because rigid structure clocks do not have the accuracy to show time dilation, at currently available speeds.

Setting the issue of time dilation aside for the moment, what is the essential difference between atomic clocks and your so-called rigid structure clocks?

To me, the issue is one of precision. Two clocks at rest relative to each other stay in sync only so well, depending on their design. The better they are at doing that the more useful they are for making measurements. This is called precision.

Atomic clocks seem not any more or less rigid than other clocks.

 

[Malvia]

Setting the issue of time dilation aside for the moment, what is the essential difference between atomic clocks and your so-called rigid structure clocks?

The issue was regarding classical rigid structure clocks where T has a well-known classical formula that depends of properties of the materials that make up the clock. Atomic clocks do not have this issue of classical formula connecting properties of materials. So while we know the T in the other frame for both atomic and rigid structure clocks, in rigid structure clocks we also can do a comparative analysis with respect to the right side of T=formula in the other frame, and analyze how it is that two sides of the formula maintain the equality.

 

[Vanadium 50]

Looking at the experimental status it would seem that Special Relativity Time Dilation verification has so far been done only for muons and atomic clocks

False.

Making false statements hoping they will be corrected is a very inefficient way to learn. It also annoys the people who are trying to help you. When coupled with a history of coming at this from an anti-relativity direction, it is a common crackpot manner of argument. You don't want to be doing the same thing, because people will draw conclusions.

We have measured time dilation in atomic nuclei and in neutron stars, both of which are many orders of magnitude more rigid than even the strongest steel. Also, listening to the pitch of such a tuning fork will be impossible, since if it is in air, the relative motion will cause it to instantly evaporate.

 

[Nugatory]

in rigid structure clocks we also can do a comparative analysis with respect to the right side of T=formula in the other frame, and analyze how it is that two sides of the formula maintain the equality.

Indeed we can, but the calculation is often tedious and difficult (especially if the formula in question is a classical approximation so we have to derive the relativistic formula from first principles before we can demonstrate that it is Lorentz-invariant and reduces to the classical formula in the limit as c approaches infinity). That's a lot of work when we already know how the calculation has to come out - if the equality isn't maintained we've made a mistake somewhere.

Something similar happens with proposals for complicated perpetual motion machines. We can spend many hours tediously analyzing the internal mechanism; but if the calculations show that energy conservation is violated, we know our analysis is wrong. The only reason to insist on seeing the calculation done is if you reject conservation of energy, which has already given you an answer with much less work.

 

[Malvia]

False.

Making false statements hoping they will be corrected is a very inefficient way to learn. It also annoys the people who are trying to help you. When coupled with a history of coming at this from an anti-relativity direction, it is a common crackpot manner of argument. You don't want to be doing the same thing, because people will draw conclusions.

We have measured time dilation in atomic nuclei and in neutron stars, both of which are many orders of magnitude more rigid than even the strongest steel. Also, listening to the pitch of such a tuning fork will be impossible, since if it is in air, the relative motion will cause it to instantly evaporate.

My statement was open and invited correction.

I am not sure what neutron star rigidity and SR Time Dilation you are referring to. What served as the clock or vibration - something rigid? Please send link.
Note that SR Time Dilation in celestial bodies has had unexplained failure too, see
https://phys.org/news/2010-04-discovery-quasars-dont-dilation-mystifies.html
https://www.newscientist.com/article/mg20627554-200-time-waits-for-no-quasar-even-though-it-should/

My OP stated "tuning fork clock" not just tuning fork. They have been available for decades -- hand-worn or larger, and later quartz clocks often have the quartz cut into tuning fork shape. We are talking normal clocks in steel case, and connected to digital display or moving hands - nothing will "instantly evaporate".

 

[Malvia]

Something similar happens with proposals for complicated perpetual motion machines. We can spend many hours tediously analyzing the internal mechanism; but if the calculations show that energy conservation is violated, we know our analysis is wrong. The only reason to insist on seeing the calculation done is if you reject conservation of energy, which has already given you an answer with much less work.

It is not useful to study a perpetual motion machine, but it is useful to study how various properties change at high speeds, with elasticity at high speeds being one of the properties that would play a role in the tuning fork clock -- and that is a field of study, as #29 mentioned.

 

[Orodruin]

It is not useful to study a perpetual motion machine, but it is useful to study how various properties change at high speeds, with elasticity at high speeds being one of the properties that would play a role in the tuning fork clock -- and that is a field of study, as #29 mentioned.

You are implicitly making the false assumption that those properties let themselves be described in the exact same way as they do in the classical limit. This is not the case and if you read #29 properly you would realize that classical descriptions need change in order to hold any meaning in a relativistic context. I believe you have a fundamental misunderstanding regarding SR and you are not going to get any further until you dispel that misunderstanding, namely that the physical properties of an object actually change when it travels at high speed. This is not the case. What changes is the description of those physical properties. In its rest frame, the object acts perfectly normally as in classical mechanics (assuming no parts are moving at relativistic speeds in that frame).

 

[sweet springs]

Why do not you think of possibility that time dilation is too tiny to observe when you are in a driving car with your wrist watch? Are you confident that the relativistic effect is absolutely zero? In experiments of 1970s atomic clocks were loaded on jet planes that go around the Earth eastbound and westbound. All The clocks including the Earth one show different times after landings as GR and SR predict quantitatively. Do not you think that wrist watches of pilots undertook the same dilations too?

 

[russ_watters]

Looking at the experimental status it would seem that Special Relativity Time Dilation verification has so far been done only for muons and atomic clocks, and not for rigid structure clocks. I suppose this is because rigid structure clocks do not have the accuracy to show time dilation, at currently available speeds.

Setting aside the other experimental verification you weren't aware of, it is true that time dilation has been tested with atomic clocks, but not with mechanical clocks. I think that was really your point.

So what? Why would scientists even bother with such a fundamentally limited and redundant experiment? It appears you believe they may get an unexpected result - that time dilation won't apply - which tells us you don't actually accept that time dilation is a real thing. Is that what this is really about?

 

[Malvia]

Setting aside the other experimental verification you weren't aware of, it is true that time dilation has been tested with atomic clocks, but not with mechanical clocks. I think that was really your point.

So what? Why would scientists even bother with such a fundamentally limited and redundant experiment? It appears you believe they may get an unexpected result - that time dilation won't apply - which tells us you don't actually accept that time dilation is a real thing. Is that what this is really about?

Regarding atomic clocks and time dilation, they keep testing again and again with more and more accurate atomic clocks. Does that mean these physicists don't accept time dilation?

If you want to do more clock tests, why not do diverse testing other type of clocks -- if that is not feasible today as seems to be then fine. But if it were feasible or in decades does become feasible it should be done for the same reason repeat testing with atomic clocks is done.

 

[Orodruin]

Regarding atomic clocks and time dilation, they keep testing again and again with more and more accurate atomic clocks. Does that mean these physicists don't accept time dilation?

No, it means that they want to test time dilation in a regime where it has not yet been tested. Switching from atomic to mechanical clocks is not doing so.

If you want to do more clock tests, why not do diverse testing other type of clocks -- if that is not feasible today as seems to be then fine. But if it were feasible or in decades does become feasible it should be done for the same reason repeat testing with atomic clocks is done.

You are still not understanding SR. If what you are suggesting were true, then different types of clocks that run at the same rate in one frame would run at different rates in another. For example, you are currently moving at relativistic velocity in the rest frame of some cosmic ray proton. We could, if we so wanted to, describe everything in terms of the rest frame of that proton where, again, you are moving at highly relativistic velocity. Do you feel any different?

 

[russ_watters]

Regarding atomic clocks and time dilation, they keep testing again and again with more and more accurate atomic clocks. Does that mean these physicists don't accept time dilation?

No, it doesn't, it means they want to add another "9" to the precision of our level of the evidence...which is good for science, plus it's useful for engineering.

If you want to do more clock tests, why not do diverse testing other type of clocks -- if that is not feasible today as seems to be then fine.

You already said the answer: because atomic clocks are more accurate than mechanical clocks. The results are better.

But if it were feasible or in decades does become feasible it should be done for the same reason repeat testing with atomic clocks is done.

No, that would not be the same reason and I would think you must know that. Your first quote asked - I thought rhetorically - if physicists don't accept time dilation. I think you know they *do* accept time dilation. But the only reason to test less accurate mechanical clocks would be if they *don't* accept time dilation.

See the contradiction?

 

[Nugatory]

It is not useful to study a perpetual motion machine, but it is useful to study how various properties change at high speeds, with elasticity at high speeds being one of the properties that would play a role in the tuning fork clock

It is no more useful. If I want to understand the behavior of a tuning fork moving at relativistic speeds relative to me, I'll calculate the frequency in a frame in which the fork is at rest and then Lorentz transform that result to a frame in which I am at rest. There are only two reasons why someone might insist on doing the calculation the hard way (working with "elasticity at high speeds") instead and they are the same two reasons that one might insist on the detailed analysis of the PMM:
1) As a pedagogical exercise, to demonstrate that if we work through all the details we will get the result that the laws of physics told us we had to get.
2) Because we don't accept the validity of the law we're applying (relativity in one case, energy conservation in the other) and are demanding more proof.

 

[PeterDonis]

Thread closed for moderators to evaluate whether further discussion is going to be fruitful since the OP question has already been answered.

Edit: at this point the mentors have decided to keep the thread closed