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Breaking Light

  1. Nov 5, 2011 #1
    "Breaking Light"

    My friend tried explaining to me that you can "break" the speed of light. He showed me a youtube video, "minutephysics" saying that if you could point a laser at the moon, by flicking your wrist, the image/spot of the laser on the moon would be moving faster than light. Is he right?
  2. jcsd
  3. Nov 5, 2011 #2


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    Re: "Breaking Light"

    No. That is EXACTLY like saying that if you look at one star and then at another star, your gaze has gone faster than the speed of light. Nothing "moves" as the beam is swept across the moon. This is an OLD canard and has to be debunked here about once a month.
  4. Nov 5, 2011 #3


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    Re: "Breaking Light"

    Special Relativity forbids physical processes that transmit some sort of information from exceeding the speed of light. Pointing a laser at the moon and flicking your wrist does not transfer any physical thing at faster than the speed of light. Different light hits the moon at the different points you point the laser at. The same light would have to move from one edge of the moon to the other for special relativity to be violated, but that is not something you can do since you're constantly sending out a stream of different photons.
  5. Nov 5, 2011 #4
    Re: "Breaking Light"

    Thank you. How you explained the different particles of light is what's moving was a better way than I could to my friend. Least I have good proof of this... I'm semi-surprised that you're asked this so frequently haha. Sorry if I annoyed you guys with such a stupid theory.
  6. Nov 5, 2011 #5


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    Last edited by a moderator: Apr 26, 2017
  7. Nov 7, 2011 #6
    Re: "Breaking Light"

    This is what happens when you try to fit something you don't know a lot about into a minute and the pixel analogy is ludicrous.
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