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Special Relativity and the existence paradox

  1. Oct 16, 2011 #1
    Do you find this argument by this author that SR implies "at least one continuum other than our own spacetime" flawed or reasonable?

    According to the special theory of relativity, observers stationary relative to one another will measure the time in the rest frame of an entity moving relative to them i.e. its proper time, to pass more slowly relative to their own i.e. the coordinate time (assuming appropriate synchronization procedures), and the faster the entity moves, the shorter its proper time is observed to be. If the entity moves at the speed of light, its proper time is observed to be exactly zero. But this implies that any entity which moves at the speed of light from the time it comes into existence until it ceases to exist must be observed to perceive itself to have a zero duration of existence in spacetime (since no time passed in its rest frame and presumably it is at rest with respect to itself). This seems very strange, as one might intuitively have thought that a zero duration of existence would be associated with non-existence, but such entities, e.g. photons, clearly exist. This has been previously pointed out by this author and termed the existence paradox .


    The author suggests that:

    Finally, it may become necessary in certain circumstances to now add the qualifier ‘in spacetime’ when speaking of observers or events in spacetime. For example, the explanation for the speed of light postulate given in this paper suggests that the speed of light postulate itself should now be stated as ’the speed of light has the same value in all inertial frames of reference in spacetime independent of the motion of the source or the observer’. That makes its domain of validity explicit, which is important because the domain of validity of the speed of light postulate also defines the domain of validity of the principle of locality, which says that nothing travels faster than the speed of light. The principle of locality should now be stated as ‘nothing in spacetime travels faster than light’. This in turn allows one to approach an understanding of its apparent violations, such as those occurring in Bell’s paradox, by asking in what way they might lie outside its domain of validity.

  2. jcsd
  3. Oct 16, 2011 #2

    D H

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    This just goes to show that philosophers have no business dabbling in physics. The divorce between the two was finalized hundreds of years ago.

    There is no existence paradox here. Just a lack of understanding.
  4. Oct 16, 2011 #3
    LOL, some physicists claim all of string theory is philosophy and physicists shouldn't be dabbling in philosophy. Which, of course, is not a scientific fact but a philosophical stance!
  5. Oct 16, 2011 #4


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    Overly specualtive posts aren't allowed.
  6. Oct 16, 2011 #5

    D H

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    The heart of the author's lack of understanding is highlighted in footnote ii in the author's FQXI submission:
    Here it is obviously assumed that it is sensible to speak of such a thing as a ‘photon frame’. One might object that since no observer in spacetime can transform to such a frame even in principle this assumption is questionable. However, there is difference between not being able to transform to a frame and dismissing altogether the possibility that it exists simply because one cannot transform to it. Claiming that it is not sensible to speak of a photon frame seems tantamount to either claiming that photons have no frames, or that photons do not exist.
    There is no such thing as a photon's rest frame. The concept is worse than meaningless.
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