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A theory for FTL communication - your thoughts please

  1. Dec 4, 2014 #1
    OK, just had a thought. And I would be grateful if someone could explain why this couldn't work:

    Place A is on a surface

    Place B in on the same surface but, say 10,000 miles away from Place A. Therefore communication between them is limited the speed of light .

    But what if, at Place A there was a laser constantly projecting a beam to Place C - which for arguments' sake is 1000 miles above the surface and equal distance between Places A and B.

    The laser's beam is by default fixed onto Place C Box 1, but at a time of asking the laser is quickly moved to shine on Place C Box 2. At this point a similar such laser which contently fires from Place C Box 2, then moves very quickly from shining at Place B box 1 (back down on the surface) to Place B Box 2

    In effect, Place A has "informed" Place B of a change in status quicker than the time it takes light to travel in-between Places A and B in a conventional method, as the lasers were already on and shining, they just needed their angle adjusting a fraction.

    This is based on the principle that lights and shadows can of course cross a distant object faster than the speed of light without violating Relativity.

    If the lasers I quoted were always on, and just needed to move slightly, and the boxes be automated to do something when light hits them, could this then = de facto FTL communication?
  2. jcsd
  3. Dec 4, 2014 #2


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    When the laser at A is shifted, the effect will not be seen at place C until a speed of light delay has elapsed. Place C, box 1 will remain illuminated for some time (about 26 milliseconds in this case) while light sent earlier from point A is still coming in, even though the laser at point A is already pointing at box 2.
  4. Dec 4, 2014 #3

    Of course!!

    Thank you!

    I'll put my Nobel prize celebrations on hold for a while
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