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Reframing the Special Theory of Relativity

  1. Mar 18, 2012 #1
    The question: is the following statement true or false?

    "If the Special Theory of Relativity is re-framed so that instead of c being constant, distance or time is the constant, it remains valid."
     
  2. jcsd
  3. Mar 18, 2012 #2

    Dale

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    I can't think of any way that could be true that wouldn't violate the principle of relativity.
     
  4. Mar 18, 2012 #3

    pervect

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    Offhand, I'd say it's not clear enough to be either true or false, unless you give more details about what you mean by "reframing".
     
  5. Mar 18, 2012 #4
    I'm asking whether the mathematics hold together. I'm not suggesting the hypothesis is true.
     
  6. Mar 18, 2012 #5

    Pengwuino

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    What does it even mean for distance or time to be constant in this context?
     
  7. Mar 18, 2012 #6
    no it doesn't

    length & time are derived from c, which is the constant, which is a speed (length x time).

    It is addressed with the terms proper time & proper length. these are your "distance [length] or time is the constant".

    So that being said you could rephrase your postulate to "the measure of proper time + proper length is constant", of course you would have to define what "proper time / length" is..again those are defined by c.
     
  8. Mar 18, 2012 #7
    What does it mean for c to be constant? All I'm asking is whether the SR, Lorentz et.al. equations can be validly reframed under the assumption that t, not c, is constant. I'm not trying to overturn physics, just get a better understanding. A yes or no answer will do.
     
    Last edited: Mar 18, 2012
  9. Mar 18, 2012 #8

    atyy

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    Then you must specify what you mean mathematically.
     
  10. Mar 18, 2012 #9

    Pengwuino

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    It means that given any inertial reference frame, [itex] {{\Delta x}\over{\Delta t}} = constant[/itex], but what does it mean for space or time to be constant? Would you mean [itex]\Delta x = constant[/itex], for example? That would certainly invalidate Special Relativity.
     
  11. Mar 18, 2012 #10
    I comprehend SR without understanding the math. I am asking if, were t to be defined as constant and c allowed to vary as t does within the current framework, would the same equations balance. I apologise for my lack of formal mathematical training, but surely this is answerable?
     
  12. Mar 18, 2012 #11

    Dale

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    Not that I know of. Particularly not given particle decay and relativistic Doppler experiments.
     
  13. Mar 18, 2012 #12

    DrGreg

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    We have lots of experimental evidence that if you take two synchronised clocks, move them apart and bring them back together, then they are no longer synchronised. So the only way your idea could work would be if we redefined time to be something other than what clocks measure.

    In a sense that's what Lorentz' aether theory did: it asserted a "true" time relative to an aether, and a "false" time measured by moving clocks. The problem was, it gave no method for detecting the aether, so no way of distinguishing true time from false time.
     
  14. Mar 18, 2012 #13
    I know that, but it's not what I'm asking. If the answer to my question is 'yes' then we would blame the variable speed of light for the phenomenon. Once again: Can the equations stand mathematically under this assumption, or do they fail to balance?
     
    Last edited: Mar 18, 2012
  15. Mar 18, 2012 #14

    Dale

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    Once again, not to my knowledge.

    I have answered this question 3 times now, it is getting irritating. Please ask something new.
     
  16. Mar 18, 2012 #15
    Thank you. Had you answered 'yes' or 'no' without qualification I'd have accepted it.
     
  17. Mar 18, 2012 #16

    Dale

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    If I knew everything then I could have answered yes or no without qualification. Since I am not omniscient I responded (3 times) that the answer was no to the best of my knowledge.

    If you are looking for omniscient responses I would recommend praying rather than posting to an internet forum.
     
  18. Mar 18, 2012 #17
    Unless somebody knowelgeable posts a contradictory answer I consider this closed. Apologies for being imprecise once again. Thank you all.
     
  19. Mar 18, 2012 #18
    We can make weird simultaneity conventions in which the one-way speed of light becomes all kinds of crazy things. So there may in principle be some simultaneity convention under which x'=x happens to be true, but I haven't worked it out. In any case, it would be nothing but a curiosity.
     
  20. Mar 18, 2012 #19

    pervect

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    There's nothing wrong with the math of special relativity, but I don't see what that has to do with your question, which still seems rather vague at best.

    Your original question seems to be along the lines of "if you call a heart a spade, how many black cards are there in a card deck", at least to me. It sort of depends on what you mean by calling a heart a spade, and it's not clear why you'd want to do such a thing. It seems rather more likely to cause confusion than anything :-(.

    Similarly, we have good concepts of what distance and time are, and how they are measured. And special relativity is about the properties of time and distance as they are commonly understood and measured - and they don't have the properties you seem to want,. It seems more productive to live with this than to get into some morass of redefining existing concepts that work well.
     
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