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Detonator paradox

  1. Mar 30, 2007 #1
    theres this problem in my book that talks about the detonator paradox, where there's one U shaped figure and one T shaped figure and theres a button for a bomb at the bottom of the U shaped figure, and the question is if the 2 figures go toward each other so that they fit, will there be a detonation. well the standard answer to this is that it will detonate because in the refrence frame where the bomb does not detonate, the end of the T will continue moving and hit the button since forces only move at the speed of light, so the bomb will detonate.
    However i looked at the other refrence frame and noticed that in the RF of the U structure, the legs of the U will collide with the legs of the T before the button is pressed while in the RF of the T, the legs of the T collide with the legs of the U after the button is pressed. could someone explain this for me?
  2. jcsd
  3. Mar 30, 2007 #2

    Doc Al

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    Staff: Mentor

    Since the two events--(1) bottom of T hitting the button and (2) top of T hitting U structure--are not causally linked* there's no problem in different frames seeing them occur in different order. (The relativity of simultaneity at work.)

    *By that I mean that one event is not the "cause" of the other.
    Last edited: Mar 30, 2007
  4. Mar 30, 2007 #3
    You haven't explained the problem very well. Also, you've misrepresented the solution (there is no "refrance from where the bomb does not detonate").
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