Is time universal? NO (and its proof)

Discussion in 'Physics & Math' started by Billy T, Aug 12, 2005.

  1. James R Just this guy, you know? Staff Member

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    That doesn't follow.
     
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  3. Physics Monkey Snow Monkey and Physicist Registered Senior Member

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    I remain confused. We take our two clocks at the same spacetime point and start them ticking. We move them around however we want and bring them back together. Once they are again at the same spacetime point, we stop both clocks. They both read their own proper time. How can the time displayed on either clock once we stop them depend on your reference frame?
     
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  5. Pete It's not rocket surgery Registered Senior Member

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    What about "proper time"? Do you think that proper time is the same as "elapsed time"? Do you think it is well defined?

    What about "time as measured by an accelerating clock"? Do you think it is well defined? Do you think it is a meaningful measure of elapsed time for that clock?
     
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  7. MacM Registered Senior Member

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    Don't speak for me please. His statement merely states that each frame believes his tick rate is standard. Aer is correct (and SRT is wrong to deny) that it is only the moving clock that is dilated. Reciprocity does not exist in time dilation.

    That is the only thing supported by emperical data and acceptable physics. The rest is rhetoric.
     
  8. Pete It's not rocket surgery Registered Senior Member

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    Like I said... you and Aer both think that SRT denies that only the orbiting clock is dilated.
    Everyone agrees that only the orbiting clock is dilated.
    The argument is over what SRT says about it.
     
  9. valich Registered Senior Member

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    This is what I am getting at, except I'm not sure what you mean by "proper time is an invariant." What do you mean by "proper time."? In any case, this endless talk about frames of reference is nothing more than a waste of intellectual argument.
     
  10. MacM Registered Senior Member

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    This is false innuendo. I damn well understand SR. I do not accept SR. That is entirely different than your statement.


    Which has nothing to do with the issue. You have refused now 2 - 3 times to reply to my question.

    I will repeat. "Simultaneity" does not and cannot alter tick rates. Accumulated time is a direct function of tick rates. Simultaneity only shifts the start or stop points, hence recorded accumulated time but tick rate is tick rate and I have shown numerous times that to claim multiple tick rates requires physical clocks to accumulate multiple times for multiple moving observers.

    Repeat Question: Do you agree that simultaneity cannot alter tick rates?
     
  11. Aer Registered Senior Member

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    Not all frames start at the same place. In fact the ground frame never even comes close to crossing paths with the satellite, unless the satellites lifetime has come to pass..

    You are confused. You are now only refering to your two predefined frames when I was refering to your claim that all frames will agree. They will not, because they will not have the same simultaneity. In other words, they are not synchronized.

    Perhaps, maybe I am considering synchronization and you are not.
     
  12. valich Registered Senior Member

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    Thanks James. Please explain.
     
  13. Neddy Bate Valued Senior Member

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    I think everyone agrees that whatever is written on the notepads is 'absolute' (and not 'relative' to any particular frame of reference).

    I wish I could follow those maths by 1100f and Pete a little better. The length contraction, time dilation, and lossed simultanaety all contribute to these calculations, but I still cannot understand what is predicted to be printed on each notepad.

    What is the difference between systems K and K' in my perfectly-symmetrical example of reference frames which are permeated with synchronized notepad-clocks??

    Assuming the clocks are identically contructed, is there any reason that the printed receipts would not be as follows?

    TimeK=1. TimeK'=15. End of notepad.

    TimeK=2. TimeK'=16. End of notepad.

    TimeK=3. TimeK'=17. End of notepad.

    They are only out of synch, but they are ticking at the same rates. Otherwise, how do you decide which frame is "really moving"?
     
  14. MacM Registered Senior Member

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    I take exception to this statement. We would not be having these arguements if that were true. James R has more than once asserted that in fact reciprocity applies to GPS.

    I miss read your comment. What you say here is agreeable.
     
  15. valich Registered Senior Member

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    Why must you assume that they are ticking at the same rate if our conception of human time is relative, but there can still be a universal time?
     
  16. Pete It's not rocket surgery Registered Senior Member

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    Hi Neddy,
    The cornerstone of relativity is that no frame is "really moving", so it shouldn't be a surprise that if you analyse something using a relativity model, you can't decide which is actually moving.

    Relativity also suggests that the K clocks and K' clocks don't tick at the same rate - that in the K frame, the K' clocks will tick slow; and in the K' frame, the K clocks will tick slow (assuming that both K and K' are not accelerating).

    This seems to be the only way that the following two things can be true:
    1) no frame is really moving
    2) There is a maximum speed that is constant in all frames
    ...which is why Einstein constructed the theory of relativity in the first place.
     
    Last edited: Oct 13, 2005
  17. Aer Registered Senior Member

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    Relativity says that there is not a universal time. Time is interlinked with space. It is other theories that suggest that there may be a universal time and still account for time dilation.
     
  18. Pete It's not rocket surgery Registered Senior Member

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    Yes, and he was incorrect to do so, [post=885182]as he has acknowledged[/post]. I suggested that perhaps he should apologise to you for making that assertion, but I guess there's too much animosity between you.
     
  19. valich Registered Senior Member

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    No, I do not agree. It is relative to your frame of reference of time, but is still absolute. Why is this so difficult to see? In space/time we have differing frames of reference but in absolute time it is the same. What is the problem?
     
  20. Aer Registered Senior Member

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    Relative = Absolute :bugeye:
     
  21. MacM Registered Senior Member

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    If so it is on his side.
     
  22. Neddy Bate Valued Senior Member

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    Hi Pete,

    I know my post sounds frightfully naive, but I think I might actually be making some ground with this.

    If systems K and K' are each 'filled' with a network of synchronized notepad-clocks, then you do not have to wait for any clocks to be reunited in order to compare tick rates. This lays bare the notion that SR can predict a dilated tick rate. It cannot because both frames are equally valid. If you disagree then simpy tell me whether it is K or K' that has the slower tick rate recorded on the notepads.

    Universal time, and identical tick rates seem to be the only logical conclusion to this non-accelerating, perfectly symmetric and inertial thought experiment.

    Of course the real universe might not necessarily have anythng like systems K and K', so SR might be just a theoretical, foundational construct that leads to greater things.
     
  23. Pete It's not rocket surgery Registered Senior Member

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    I'm sure I saw someone call someone else an asinine prick yesterday... sounds like animosity to me.
     

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