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If t=0 how does a photon get absorbed?

  1. Dec 15, 2014 #1
    There are many things that confuse me, my wife, my job, but at the moment, mostly a photon.

    I am a photon, t=0, since v=c. Ok, but t=0 is accurate to infinity to the power of infinity, for a photon. it doesn't even aproche infinity, it starts there.

    To be causal, in any other inertial frame (and for simplicity, let's say all frames are inertial in this thought expiriment) t= time for photon to get to some destination for that destinations observer (or electron, maybe). In other words, the light cone of the photon.

    === edit for clarity ===
    inertial frame, as i understand it, is a non-accelerating frame
    === end edit ===

    So that kind of explains wave particle duality of photons, the photon experiances being everywhere it could be, until it interacts with something (decay, electron, etc...)

    *BUT* if t=0, how in the physics does it manage to do anything? are photons the same sort of thing as shadows (for instance, cast by a planet, onto a moon, traveling at ftl speed)? if not, should they be subject to a slowdown, even of less then a plank length, to allow thier clocks to tick, for some interaction?

    If t=0, and v=c, isn't your experiance equal to being the aether, or maybe the vacuum energy? and isn't any observer going to at best notice an increase or decrease (depending on the math) in vacuum energe, over time - as more and more photons (gravitrons, etc...) become the aether across thier light cone.

    Shouldn't c be some "perfect speed", and the actual speed of light in a perfect vacuum be something slightly smaller?

    Maybe it's because they interact in space, while t=0, but in that case, shouldn't light always interact with the first potential suitor?

    Anywho, my first post here, many internet searches deep, minimal university experiance in the field, but please include both formulas and plain explinations or examples... no need to turn on spell check thoguh :P Appologies :)

    Also, not interested in 'you can't go luminal' replies, we are talking zero rest mass here, and my confution comes from zero ~time~ to interact, or be causal. For both photons, and wife XD
    Last edited: Dec 15, 2014
  2. jcsd
  3. Dec 15, 2014 #2


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    Time is what a clock measures. You can't build a clock out of just photons, you need something with mass to build a clock. Something with mass cannot go at the speed of light. Therefore, time does not apply to a photon. It's not that time is zero for a photon, the concept is meaningless. So don't waste your time trying to analyze time for a photon. (You cannot be a photon.)
  4. Dec 15, 2014 #3
    If I understand you correctly, the photon has no understanding of time, but the X that absorbes it, at least has an understanding of space, related to that photon, and causal enough... So a photon will travel it's light cone at it's t=0, and an absorber of the photon willl simply be the first "space" that a photon could be causal too.

    In that case, shouldn't every atom in the visible universe contribute to distortions of light, and other causal effects?

    Perhaps that question answers my dilemma.
  5. Dec 15, 2014 #4


    Staff: Mentor

  6. Dec 15, 2014 #5


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    If you understood me correctly, you wouldn't repeat your mistake in bold.

    That question is incomprehensible to me. Even without considering what you said before your question, why do you bring up "every atom in the visible universe" and what are "distortions of light"?

    It seems to me that you are really trying to understand an issue with quantum mechanics using Special Relativity, is that correct?
  7. Dec 15, 2014 #6
    Thanks DaleSpam, your reply explains why it's an unusual question.

    And thanks ghwellsjr, I was unable to understand your first attempt, but I think I get it now :) If t=0, or v=v=c=0 (as in Dale's link), then a lot of non-sense happends.
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