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.(adsbygoogle = window.adsbygoogle || []).push({});

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....

t'=#1(t-vx)

x'=#1(x-vt)

t''=#2(t-wt)

t''=#2(x-wt)

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

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

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# Jack and Jill twins

Can you offer guidance or do you also need help?

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