The regarded idea was that if you travel by the speed of light your body will age less and less, because of the differences in the interractions of time. However, this "theory" is incorrect, because if anyone has every study the hyperbolic differences between humans and other animals, that the faster your hyperbolic level is the faster you age, which is why a turtle has a slower reaction time than a human, yet it can live for a very long life. Have you ever notice that when you travel in an airplane that it appears to be longer than expected to get from point A to point B, well that is because, since you are travelling in a faster speed than simply standing around on the ground or in the air, if you have a jetpack, or if you in a helocopter and it stay still, your brain stimulates a higher frequency of interractions with your body in response to this change. If your brain did not do this you would be acting more slowly in an airplane, it would appear to not take as long as it would seem. Everyone should know that it is the brain's interractions with the body that stimulates hormones and that causes you to age, grow, ect, ect, ect... Imagine that if someone did manage to make an airplane that would stay in the air forever and that airplane would continue to travel at the same 2000 mph or more in the sky, then how old physically would that person become in the next twenty years since that airplane had departured? Another question that has plagued my mind, is if you travel to the edge of the universe and you kept travelling onward, then what would explain if you so happen to find the edge of what appears to be another universe? Could you have some how manage to reach another universe or are you still in the same universe, yet you are on the other side? Like if you travel around the world, as it was once told to be flat.