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Do waves/particles of light experience time? Awesome videos!

  1. Jun 13, 2012 #1
    I'm new to studying this type of physics. I've been watching videos and reading about quantum physics and relativity. This channel has great videos about quantum physics and relativity. But can someone explain the first minute or so of this video to me?

    (apparantley I can't post links to this site because I don't have ten posts so remove the spaces before and after each dot)

    www . youtube . com/watch?v=z6pzEh6pE3A&feature=plcp
    If light is traveling at the speed of light then shouldn't it not experience time? So why then do people say it takes 5 minutes for light from the sun to reach earth?

    Currently I think it is because light travels both through space and time and therefore experiences both. Just watch the video and you'll understand what I'm asking.

    Thank you!
  2. jcsd
  3. Jun 13, 2012 #2


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    This is the difference between superficial understanding of Special Relativity versus an actual understanding. The latter forces you to actually tackle the problem quantitatively and look at the DETAILS.

    You are mixing reference frames. When we say light takes such-and-such time to travel, we are talking about light traveling IN OUR REFERENCE FRAME over some distance. It is only when you try to TRANSFORM into the reference frame of light (i.e. you do a Lorentz transformation to a frame of reference moving at v=c, which is a dubious thing to do in the first place) can you then say that the time "dilation" in that frame AS VIEWED FROM OUR REFERENCE FRAME indicates that t=0 in that frame. This is a crucial and subtle difference.

    That is where there is a lot of primed and unprimed coordinates being used in SR.

    Moral of the story: you cannot understand physics simply by watching or reading. You have to sit down and work it out and grind through several different types of situations, scenarios, and problems.

  4. Jun 13, 2012 #3
    Thanks! So what books can you recommend that will teach me how to do the math and science so i gain more insight into relativity? I only have taken calc 1 so far but I'm deffinately willing and wanting to learn more
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