im at a youtube discussion and if it would be possible i would like anyone with understanding of Einsteins special theory of relativity to give me some information on a certain issue: it is about the famous train experiment, the one about simultaneity. if you use a rod to mesure a distance from the front of the train to the middle, it would mesure a shorter distance than a slower reference frame because light takes less time to arrive at the middle from the front, that is, the front tip "mesures first". what about from the back to the middle? i know from high school that distances shorten in the direction of the movement, but, if it is the fact that light arrives first that determines lenght and time, what about the light rays that take longer from the back to reach the front?(adsbygoogle = window.adsbygoogle || []).push({});

another problem i have is with this, posted by a youtube user:

"Very good loupax! You're right! This video is incorrect in it's depiction of the paradox. The paradox is that BOTH observers see the light hitting them AT THE SAME TIME and BOTH observers see the SAME light hitting the other person at DIFFERENT TIMES. Watch "The Mechanical Universe and Beyond", episode 42 of 52, the Lorentz Transformation for a full explanation."

is this true?

thanks in advance

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# Need a little help please

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