Han and Greedo are at the rear and front of a relativistic train travelling at speed
u (with equivalent Lorentz factor gamma). As the train passes through a station (without
slowing), Han and Greedo are observed by the ticket collector on the platform to re
their laser blasters simultaneously. She also measures the length of the train to be LS.
Let the station and ticket collector be at rest in inertial frame S of the \standard
con guration", while the train, Han and Greedo are at rest in S0. De ne the origin
x0 = 0 of S0 to be Han's location at the rear of the train, and the origin x = 0 of S
to be the position of the rear of the train at the moment t = 0 in frame S when the
lasers are red.
i. Write down the (t; x) coordinates of the events corresponding to the ring of the
lasers in frame S, and transform them into S0 coordinates.
ii. Calculate the times in S0 when Han and Greedo each see the other fifi re their blaster.
iii. Comparing your results for parts (i) and (ii), could either Han or Greedo have red
their blaster in response to seeing the other shoot first?
