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techdirect
Aug9-09, 12:55 AM
Hi all,

I am not a physicist. Some engineer friends of mine and I have a question about special relativity in two dimensions. To set it up, there are 2 lights floating in space parallel to the x axis and a space ship is traveling at .8c flying parallel to the y axis towards the midpoint of the line connecting the lights. Then at some time, t, an observer, o1, between the lights at the midpoint flashes both of them simultaneously.

I drew a quick diagram which is attached.

1. The observer o1 will see both flash simultaneously

2. At a different time t', the crew of the space ship will also see both flash simultaneously because of the symmetry of the problem.

Is our understanding correct?

tiny-tim
Aug9-09, 05:08 AM
Hi techdirect! Welcome to PF! :smile:
1. The observer o1 will see both flash simultaneously

2. At a different time t', the crew of the space ship will also see both flash simultaneously because of the symmetry of the problem.

Is our understanding correct?

Completely! :biggrin:

(and, more generally, even if the spaceship was not in line with o, but was still moving parallel to the y-axis, even though it would not see the flashes at the same time, it would calculate that they happened at the same time)