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Question about Photons.

  1. Jun 29, 2011 #1
    I am posting this under the belief that velocity affects mass and time, if my understanding is incorrect please correct it.

    If a photon is travelling at C then theoretically does it have an increased mass compared to a photon that is "at rest"?

    And if a photon is moving at C then does it have an infinite "life span"?
  2. jcsd
  3. Jun 29, 2011 #2


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  4. Jun 29, 2011 #3
    It is obvious that a photon does not have a "sense" of time. But thanks for the link.
  5. Jun 29, 2011 #4
    I guess you're asking if a photon, observed by external 'stationary' (which will always be stationary to light's velocity of c) system appears to suffer time dilation, in this case infinite. Obviously no, because they can be destroyed in a matter of attoseconds and less.

    But photons are massless and not party to the whole relativity time, length, mass thing anyway.
  6. Jun 29, 2011 #5
    I agree. Photons exist only at c or not at all.
    This curious phenomenon is not seen elsewhere in nature(to my understanding that is)

    However, that fact that a photon has no "rest mass" helps, somewhat, in our query as to how it can go from 0 to c instantaneously.
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