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B What if the speed of light were not constant?

  1. Mar 25, 2017 #1
    Could einstein's theory be completely wrong if we discovered that the speed of light is different in an another galaxy ( speed light isn't constant) and if we proven that there is particles or objects which moves faster than light by 100 or 1000 times?
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  3. Mar 25, 2017 #2


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    Hello Lcev, :welcome:

    I suppose so. What makes you aks this and what do you think ?
  4. Mar 25, 2017 #3


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    You can never say 'never' but all measurements have led us to believe that c is a universal constant at this stage in the development of the Universe. There is a lot of evidence for this in the spectrum of light that we receive from millions of light years away. Exactly the same structure is observed in the spectrum of the light that's received and that strongly implies that the quantum mechanics at work out there is exactly the same as the QM we use here. If c were different, you would expect everything else to look very different and it doesn't.
    PS "Completely Wrong" is the 'completely wrong' (haha) way to describe something that works so well in our part of the Universe. The only term you should use could be 'limited'.

    Read up about it after searching on "The speed of light constant" etc.
  5. Mar 25, 2017 #4

    Vanadium 50

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    It's true that if we had different observations, we would invent different theories and models to explain them. But we don't have different observations.
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