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Jack and Jill twins

  1. Feb 25, 2004 #1
    Suppose we have a closed/periodic universe (t,x) ~ (t,x+L) where L is the circumference of universe. Jack and Jill set off from x=0 with different velocites. From time to time Jack and Jill's path will cross.

    I having trouble getting the right calculutions to find what jack and jill can infer about their velocities and L.

    Am i right in saying i have 3 knowns (relative velocity of jack and jill, time that has elasped for jack, time that has elasped for Jill and 3 unknowns (jacks velocity, jills velocity, L (circumference of universe)) with the following equations....



    where #1 is (1-v^2)^-1/2 etc

    and u = (v+w)/(1+u*w) (relative velocity of jack jill)
  2. jcsd
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