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Are the photons we interact with actually anti photons?

  1. Dec 21, 2012 #1
    I know that there are no anti photons since a photon is its own anti particle but if the theory of antimatter is matter moving in the opposite direction of the 4th dimension (moving back in time), then are the photons we interact with actually photons that move in the opposite direction in time? Thus making us look back in time the farther we look? Then is the difference between photons and anti photons the fact that they move in a different direction in time?
     
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  3. Dec 21, 2012 #2

    Drakkith

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    Antiparticles are not moving backwards in time. I believe it was Feynman that claimed that the math could be interpreted as a regular particle moving backwards in time, but as far as I know there is no real theory on this and he himself never claimed that this was actually happening.

    Also, the fact that we look backwards in time the further away we see is because of the finite speed of light. If it takes 5 years for light to reach you, then anything you see from there happened 5 years ago. This has nothing to do with antiparticles.

    When we say photons are their own antiparticles we mean that there is no separate particle that could be called an antiphoton. You don't have photons and antiphotons at all. You ONLY have photons.
     
  4. Dec 21, 2012 #3

    Bandersnatch

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    Think of it this way: when you receive a letter sent to you a week ago, was it really travelling back in time?
     
  5. Dec 21, 2012 #4
    That makes sense. I know why light is delayed from the 3D perspective but i was trying to look at it on a greater scale. But yeah i guess we dont really have enough proof to claim that antimatter moves in a different direction in time
     
  6. Dec 21, 2012 #5

    Drakkith

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    I would ask what moving backwards in time even means. What other laws would be different, if any?
     
  7. Dec 21, 2012 #6
    Well according to M theory we are 6 dimensional beings. The 4th dimension represents time for us so imagine the universe as a collection of 3D snapshots all put side by side in a big line. Two points on that line represent the beginning is the big bang and the end of the universe. We can only be in one 3D snapshot at a time but we see snapshots in different points on the 4D line.The farther we look, the farther the snapshot is on the 4D line. I was trying to add photons to the picture thus why i made this thread :P
     
  8. Dec 21, 2012 #7

    Drakkith

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    Unfortunately M theory is not an accepted mainstream theory, so whatever results it comes up with are irrelevant at the moment.

    Ah, I see why you asked the question. That's pretty much my point though. If particles did indeed move backwards in time, what would be the result? Would their spatial movement be different? Would their properties like charge and mass be different, or even opposite of what they are now? Would those results even make any sense? (Such as negative mass) I'm not really asking any questions here, I'm just saying that if you think of something moving backwards in time, would you even know how that would work? And how would you be able to tell? How would those effects show themselves in the real universe? Hence why I don't believe that antimatter is normal matter moving backwards in time. Please, don't start speculating on every point I made here, as speculation on this would be against PF rules as far as I know. (Unless you know of some Quantum Mechanics stuff that deals with this)
     
  9. Dec 21, 2012 #8

    A.T.

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    There is a lot of confusion about that "anti-matter moves back in time" idea. I think what is meant there is moving back in proper-time, not in coordinate time. So it is not about time travel, but a certain geometrical interpretation of space-time, where proper-time is a dimension, not coordinate time. It is visualized here:

    http://www.adamtoons.de/physics/relativity.swf

    In this picture a photon doesn't move at all in (proper)time, because it doesn't age. It moves only through space. Therefore there can't be anti-photons, because photons are neither matter nor-antimatter, but rather "on the edge" between them.
     
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