>>11209101good question. essentially weird stuff happens if you go near the speed of light.
lets start with a little thought experiment. say you are driving on the highway with 50 km/h and your buddy is sitting at the side of the road watching you. now lets say you drive past him and right when you zoom past him you throw a tennis ball out of the window, in the same direction you drive with 50 km/h from your perspective. what will you see and what will your friend see?
essentially the ball moves away from you with 50 km/h but your friend sits at the side of the road so for him the ball is moving away with 100km/h because the speed of the ball and the cars speed add up to 100km/h.
so basically the speeds add up. but now comes the weird part. the speed of light in a vacuum is actually constant. for everyone. all the time. no matter what you do. so to take the same thought experiment as before: you drive your car with half the speed of light and your buddy sits at the side of the road. if you point a laser pointer in the direction you drive then for you the light is moving away from you with the speed of light, but for you budy it should move with 1 1/2 times the speed of light right ? nope even for him it still only moves with the speed of light.
sounds weird but its the truth. now hos is this possible you ask? well the anser is lengths and time change when you get close to the speed of light. additionally these relations forbid you from going at the actual speed of light. you can only get very close to it. and if you tried, you'd find that the energy needed to become faster gets higher and higher.
so what does all of that mean? first of all you can't actually travel at the speed of light, only very close to it. and secondly, to describe it qualitatively, time will slow down for you if you travel very fast, or to put it differently everything around you will happen faster.
(1/2)
