@TM:
I am sorry, Sir GeZe, but Einstein said Time Travel should not be possible. In Einstein’s Theory of Relativity, it states that nothing can go faster than the speed of light.
that is correct.
Einstein showed that was no such thing as instantaneous interaction in nature, but only a maximum possible speed of interaction. This is the speed of electromagnetic interaction, which is the speed of light or 300,000 kilometers per second. The second part of the Theory of Relativity states that the speed of light is universally constant and the same for all inertial observers no matter how they move.
That is not totally correct. There is instantanous interaction (see: Einstein, Podolsky and Rosen; entangled states), but you cannot use this interaction to transmit information or even matter, but technically it still is an interaction. This is a quantum effect, that is not covered by the Theory of General Relativity.
As an object nears the speed of light, its relativistic mass increases until, at the speed of light, it becomes infinite. Accelerating an infinite mass any faster than that is impossible, or at least it seems to be right now.
This is technically speaking incorrect, though a polular interpretation.
Plus of course: The first only holds for objects with a finite mass at rest. Photons for example move at the speed of light, and have no “rest mass”.
However, there is a mathematical possibility of particles that travel faster than the speed of light, called tachyons. There is mathematical evidence for this, though we have yet to detect any of them. Tachyons cannot slow down to below light speed, just as we cannot accelerate to above the speed of light. Perhaps, Herr F_alk could tell us more about this?
Sorry, not too much, except that that is true. Tachyons are theoretically predicted, but i don’t know if there is any way or proposal of how to detect them. Therefor, they will stay where they are: in the space of theoritical objects.