I'm not educated in physics but I'm trying to learn some things. As I understand it light speed is the speed limit of the universe because objects gain mass as they accelerate and it takes more and more energy to continue accelerating, as the object approaches light speed it's mass begins to reach infinity and its impossible to have enough energy to go faster. Ok so if I accelerate an object and the mass increases where is this mass coming from? Just guessing I would think it has to come from the kinetic energy. If not where else? If that guess is right then it is correct that adding energy to an object increases it's mass? Or am I getting it totally wrong. But if I'm right and kinetic energy increases mass, then wouldn't thermal energy do that too? And would that increase the gravitational force of the object? If mass does increase it has to right? That would explain why time is effected by speed, because gravity gets stronger the faster you go. But I'm probably just an idiot.