Firstly, im sorry if a similar question has already been posted, but I couldnt find the answer anywhere.(adsbygoogle = window.adsbygoogle || []).push({});

Im not an expert by any means, and my confusion might be caused by my complete misunderstanding of special relativity, so Ill start by explaining what I think an example of special relativity is, which could be complete rubbish, I dont know.

Take 2 people, A and B. A is standing stationary, and observing B, who is travelling at 0.99c, aswell as a beam of light travelling in the same direction to B. Person A observes for 1 year (relative to himself). He observes that the light beam travels exactly one lightyear, and person B travels 0.99 of a lightyear. However, according to person B, the beam of light has only travelled 0.01 of a lightyear further than him, and as light always travels at 1lightyear/year the time that has passed according to Person B is 0.01 of a year (3.65 days). I hope this makes any kind of sense.

My question is, say both people A and B are also observing a beam of light travelling in the opposite direction to person B, starting at the same position as the starting point of person B. person A would observe a total distance between Person B and the new beam of light after a year to be 1.99 lightyears. But we know that if it takes a year for person A to observe something, it takes person B only 3.65 days, therefore the relative speed of the new beam to person B is 199c. This makes no sense. What have I done wrong?

sorry if this is a silly question/already been answered/the ramblings of a madman, but id be very grateful if anyone could explain this problem to me

thanks

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# Relativity problem thats been bugging me

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