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A rocket is in uniform motion and is of length, as measured in a stationary frame, of 300,000 km
When the back end of the rocket, which is moving left to right, as seen from the ground frame, reaches a point which is directly above a post on the ground both lasers are fired simultaneously as time is perceived in the rocket's frame.
There is a clock at the middle of the rocket and a clock on the ground in the middle of the two posts, both of which are visible to both observers in both frames. Both clocks read zero as observed from both frames at the time when the lasers are fired.
There is a clock at the middle of the inertial rocket and a clock on the ground in the middle of the two posts, both of which are visible to both observers in both frames. Both clocks read zero as observed from both frames at the time when the lasers are fired.
At what distance markings do each observer see each target hit by its corresponding laser beam, and what are the readings on each clock when each happens, as perceived by each observer.
The problem doesn't involve the actual times required for the light to reach the observers' eyes from the targets and clocks, it's assumed to be instantaneous for our purposes
Can you perform any kind of relativity related manipulations which will result in both beams appearing to travel at 300,000 km/s to both observers?
One beam in one direction would be easy, but can you do it with two beams in opposite directions at the same time?
Let's say the laser on top of the rocket is at the left, or back, end and fires to the right, in the direction of travel of the rocket. I conclude that it will hit its target at the 450,000 km mark, which is at the right post itself, and the bottom laser will hit its target at the 150,000 km mark and both will be at the time of 1 second on the rocket clock.
One immediate consequence is that the lasers were NOT fired simultaneously in the ground observers frame.Quote from: Centra on Yesterday at 18:25:24"There is a clock at the middle of the rocket and a clock on the ground in the middle of the two posts, both of which are visible to both observers in both frames. Both clocks read zero as observed from both frames at the time when the lasers are fired." Sorry, that is not possible. The clock on the ground can read 0 when the first laser fired but it must read +1 unit of time when the second laser fired. Anyway, there's nothing much you can do after that, the problem is an assumption of simultaneity in every frame. The remainder of your reasoning might be good but it just doesn't matter. The initial input was impossible or invalid.
This is the first problem. These clocks are not in the presence of the event of the laser being fired, and thus don't define a specific event at which they read zero.
Like I said to Eternal Student, consider the rocket frame to be stationary and the ground frame to be moving at 150,000 km/s past it to the left, ignore the distance markers for now, what would the ground observer see as he moves past while keeping his eyes focused on the rocket?
Like I said to Eternal Student, assume that both lasers are fired using a single button, not two separate ones. You answer that simple question and we'll proceed from there, same for Eternal Student.
It would make things simpler, though, if you just describe what the ground observer would see and then I respond to that.
So by your logic he would see the two lasers firing at separate times even though we know that the lasers were fired using a single button in the rocket.
I have a thought experiment type paradox, related to the Theory of Special Relativity, which I would like to see if anyone can resolve, the apparent paradox of light seemingly being sped up or slowed down to other than normal velocity in one inertial frame of reference when viewing light beams generated in another inertial frame in relative motion to it.