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A question about the principle of special relativity

  1. Feb 1, 2009 #1
    the theory told us, there is no priority frame of reference. I have two comprenhensation of these sentence. 1, we could find no physics way to measure or make sure the exsistence of priority frame of reference. 2. the existence of priority frame of reference conflicts with relative principle. if the relative principle stands right, the must be no priority frame of reference. which one is right?
    maybe this two way of understanding conbine the same meaning or law. could anyone give me some instructions
  2. jcsd
  3. Feb 1, 2009 #2


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    The second is the right interpretation. The first one may be read as if there might be some preferred reference frame, but we're just unable to find it. The principle of relativity really says that whatever (equivalent) reference frame I pick, all my physical laws will be the same (and to do physics, that's all that matters, even though I could discern between them by talking about "my" frame and "your" frame, or labelling them A, B, C ...).

    So indeed the very existence of a (physical) priority frame of reference, would mean that we would have to have some indication of it in our theory (for example: this formula is only valid inside or outside that particular frame) which simply contradicts the axiom that there is no such dependence in the formulas.
  4. Feb 1, 2009 #3
    thx very much.
    could I take your explain as official veiws? or does the physics specialist agree with this explanation.

    I'm still not certain about it, because some other day I read an article about the theory combining priority frames and relative principle .
  5. Feb 1, 2009 #4


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    Do you remember where you read it? The principle of relativity definitely says all the fundamental laws of physics should be the same in different frames, but there have been speculations that there could be fields filling the universe that formed shortly after the Big Bang with a randomly-determined rest frame (i.e. there's nothing in the laws of physics that says it couldn't have been any other frame, so even though experiments involving this field might give the appearance of a preferred frame, the frame isn't actually preferred in terms of the fundamental laws). There's a good article about such speculations http://physicsworld.com/cws/article/print/19076.
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