I think I see now... to the outside observer, even if you did constantly accelerate, you would be constantly accelerating more and more slowly as time slowed down to the outside observer, so as you approach the speed of light, time slows down for you, but speeds up for everyone else, so you...
Okay... I get it barring the gammas and lambdas that weren't really explained, but how does this prevent a rocketship with infinite fuel from reaching the speed of light just by running its thrusters constantly in a vacuum for the appropriate amount of time?
So if relativistic mass goes to infinity, that is the mass to an observer. What about the mass to the object itself? Say I'm cruising along at .9c, my relativistic mass is some 700 times normal, but I can still run, jump, and kick aboard my... uh... millenium falcon, which I wouldn't be able...
Okay, I understand that if you dedicate some motion to one dimension at a constant rate you consequently pull motion from another dimension. Like driving at an angle rather than a straight line traveling a longer distance to a said stopping line (traveling in two dimensions rather than one). I...
Why only 2-D?
My question, Livingod, is why only consider the motion in one spatial dimension and the time dimension? What about, say, a rotating disc, which must by definition move through two spatial dimensions? Or an expanding/contracting object (say a collapsing star)? What happens when...