How do scientists know that traveling faster than the speed of light causes time travel?

What did they use to demonstrate or observe time travel if we can't travel faster than the speed of light?How do scientists know that traveling faster than the speed of light causes time travel?Einstein's light clock thought experiment was used to construct the theory of special relativity. In it he developed equations for time slowing down as perceived by outside observers when a reference frame travels significant fractions of the speed of light. This is called time dilation.



Now, when you exaggerate the equations of special relativity and plug in speeds greater than the speed of light, you get that outside observers will perceive the reference frame's time to go backwards.



Of course though, if you pay attention to the more important equations of relativistic momentum and relativistic kinetic energy, you observe that it is physically impossible to travel superluminal speeds. It requires infinite energy to accelerate bodies of ordinary mass to the speed of light, and it will require a superinfinity complex number amount of energy to get bodies of ordinary mass beyond the speed of light...a completely invalid use for complex numbers.How do scientists know that traveling faster than the speed of light causes time travel?you can't travel faster than the speed of light if you have a rest mass (even with 0 rest mass a particle can only travel faster than the speed of light through certain media)How do scientists know that traveling faster than the speed of light causes time travel?Subatomic particles moving near the speed of light take longer to decay, by the amount of time predicted by Special Relativity. Accurate clocks have also been flown on jets to show that time passed more slowly for them vs. the same clocks at rest on Earth.