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Clock-experimental proof of special relativity

  1. Jun 27, 2012 #1
    clock-experimental "proof" of special relativity

    It has been said in objection to special relativity that the atomic clocks changes in measurements in different speeds is only a proof of change in measurement between clocks and not of time passage. This would object to the conclusion that simultaneity is relative.

    However it is reported that the rate of an ideal clock is not affected by it's acceleration. It's mentioned that there are indeed experiments done to prove this. Thus the escape rout is ruled out. I want to know how they know this?

    If this is really true then I see no reason as to why anybody would object to the block-universe(and thus determinism) given the experimental proof of atomic clock changes(with difference of speed) which have been verifed over and over again even in recent times.

    The only reason then for the changes in the clocks measurements can only be because we live in a block-universe, were all events already exist(since no universal now exist)

    "If it looks like a duck, walks like a duck, and quacks like duck- it's probably a duck"
    Last edited: Jun 27, 2012
  2. jcsd
  3. Jun 27, 2012 #2
    Re: clock-experimental "proof" of special relativity

    I'm a bit confused, but I'd like to point out that relativity (and simultaneity) do not disprove determinism, Quantum Mechanics does. GR (and SR) fit perfectly with a deterministic world.

    Its hard to argue with the argument of the deniers of relativity, because it seems like they are disagreeing for no reason. But I would respond by saying that if you measure the dilation of a thousand clocks at a thousand different speeds and each dilates exactly according to relativity, anyone who says that's a coincidence is crazy.
  4. Jun 27, 2012 #3
    Re: clock-experimental "proof" of special relativity

    Your post, as formulated , is incomprehensible. What are you trying to say?
  5. Jun 28, 2012 #4
    Re: clock-experimental "proof" of special relativity

    Read this..


    And now with reference to the atomic clock experiment(one on the ground and one travelling on a plane). they say that we cannot explain away the difference in measurements(from one clock on the ground and the one on the plane) by acceleration.

    The passage of time really does change depending on the speed, so therefore a persons past could be another persons future. Therefore all event's already exist since there is no universal "now". We are only waiting for the future events that are already set in stone(and some can reach them faster than others).

    Yet when I google the clock-hypothesis it is clearly stated on wikipieda that it is an assumption. So therefore the objection by "presentism" that it's a physical phenomenon on the actual clocks seems to still be valid.
  6. Jun 28, 2012 #5
    Re: clock-experimental "proof" of special relativity


    General Relativity doesn't allow for this. In the rare cases that it does, we call these 'time machines' and note that it requires the existence of a type of matter that by all accounts does not exist.
  7. Jun 28, 2012 #6
    Re: clock-experimental "proof" of special relativity

    I was talking about special relativity.

    <"The relativity of simultaneity implies that the future is determined (in a non-causal sense) in the following way. Let us say that you at this moment are event A. That is, your present self — what you are doing, thinking, observing, and so on, at this moment — is A. Let's also say that there is an observer traveling in a very fast spaceship, who at this very moment (from your frame of reference) is event B. Now for B, that is, for the spaceship traveler at this moment, there is an event C which, from B's perspective, lies in the past. The interesting thing is that it is possible for C to be an event which, from A's perspective, is still in the future. That is, C hasn't happened yet as far as you're concerned. Nonetheless, there is someone right now (again, from your perspective) who regards C as having already occurred. And if that is the case, then how can C be avoidable?

    If an event which is in your future is in someone else's past, and that someone else is in your present (or even in your past!), then it is inevitable that the event will take place. Event C must come about, no matter what. And this scenario can in principle apply to any future event. Thus, all future events are determined. ">

  8. Jun 28, 2012 #7
    Re: clock-experimental "proof" of special relativity

    That doesn't either. Also more generally special relativity is encompassed by general relativity.

    Reading what you said, I realized you are correct, but I was too. Usually when I deal with stuff like this it is with people who think it means time travel, so I apologize for disbelieving you. Yes this is possible, but in this cases it means no information can be passed from someones future to someones past, just that two observers can independantly witness an independant event at different times.
  9. Jun 28, 2012 #8
    Re: clock-experimental "proof" of special relativity

    The above is a crackpot link, I thought such links are not allowed in this forum.

    Who is "they say"? Where did you read that?

    This is incomprehensible.
  10. Jun 28, 2012 #9
    Re: clock-experimental "proof" of special relativity

    "Who is "they say"? Where did you read that? "

    "Is there an alternative to the block-universe" google that... go to page 18 if you are too lazy to read the hole thing.
  11. Jun 28, 2012 #10
    Re: clock-experimental "proof" of special relativity

    Yes, I got another crackpot website, I see your game now. Bye.
  12. Jun 28, 2012 #11
    Re: clock-experimental "proof" of special relativity

    You say it's crackpot links with no additional reference as to why that is case.
  13. Jun 28, 2012 #12
    Re: clock-experimental "proof" of special relativity

    Instead of arguing about legitimacy, could I ask the OP to restate his question, if it has not been already answered.
  14. Jun 28, 2012 #13
    Re: clock-experimental "proof" of special relativity

    Does the lack of absolute simultaneity in special relativity prove determinism ?.

    It appears you have to deny the premiss, if there is no universal "now" for all observers then all events truly exist. IF all events exist determinism is true.
  15. Jun 28, 2012 #14
    Re: clock-experimental "proof" of special relativity

    Your question is logically equivalent to "Does the fact that the Moon is round prove that you should not eat spaghetti on Fridays?"
  16. Jun 28, 2012 #15
    Re: clock-experimental "proof" of special relativity


    "In 1966, C. W. Rietdijk published "A Rigorous Proof of Determinism Derived from the Special Theory of Relativity." It purports to prove that the world is pre-determined because of an argument from special relativity called the "relativity of simultaneity." "

    And then of course we had another loser named Roger Penrose with his "Andromeda paradox" based on the same idea.

    I seem to be in good company even if I am wrong:)
  17. Jun 28, 2012 #16


    Staff: Mentor

    No. Modern quantum mechanics (QED and the Standard Model) is non-deterministic but compatible with special relativity.
  18. Jun 28, 2012 #17
    Re: clock-experimental "proof" of special relativity

    You are wecolme to mention an interpretation compatible with special relativity while rejecting determinism.

    Please note that by "determinism" I mean that all events that ocurred had to happen, and they way the did. They were written in stone. Following a "Causual chain" of events are not neccesary for determinism, this is an old misconception. So we could have events without a cause, as long as they had to happen it's determinism.

    <"Causual chain"> determinism may very well only be a partial depiction of the universe, but that does not falsifiy determinism.

    Take for instance a universe without time, in such a world causuality is irreleveant because all event's already exist.. so what happens tommorow is and always have been decided (determined).
    Last edited: Jun 28, 2012
  19. Jun 28, 2012 #18


    Staff: Mentor

    I am not interested in interpretations of QM, just the math.
  20. Jun 28, 2012 #19
    Re: clock-experimental "proof" of special relativity

    You were the one claiming it was compatible with special relativity without a block-universe.

    If you are only interested in the math then I don't see why you are in this thread.
  21. Jun 28, 2012 #20


    Staff: Mentor

    Re: clock-experimental "proof" of special relativity

    My post did not refer to any interpretation. QED is non deterministic, meaning that a complete specification of the state of a system at some point in time is not sufficient to uniquely predict the state of the system at a later time. QED is also compatible with special relativity, meaning that its equations are invariant under Lorentz transformations. So, mathematically, special relativity does not imply determinism. It is not a matter of interpretation, just the math.
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