Do you believe there are species that have mastered FTL travel?

[longship]

26. I doubt it.

Especially since the relativity equations seem to be so robust. Yes, they are still classical physics (ie, not quantum). Nevertheless, just as relativity did not cancel Newtonian gravitation -- it only expanded its applicable domain -- I expect the relativity will hold in the future.

I may be wrong about this, but I doubt it.

Quantum doesn't hold much hope for FTL travel either, in spite of quantum effects seemingly traveling FTL. These results are highly contrived and nobody involved in the theory or experiments believes that information can be transmitted by such a process. In fact, the theory specifically forbids such a thing from happening. If there can be no information transmitted by quantum entanglement, than certainly one cannot use it to transmit a solid object. (Which, in any case, would not act as a quantum object simply because all quantum effects average out to null for any object sufficiently large to be any use.)

Physics does not advance by replacing whole bodies of theory. It advances by modifying existing theory. That's the way modern science works in general. We'll never see a time that evolution will not have happened. Similarly, we will likely never see relativity falsified in whole.

C is the speed limit of the universe. That fact is woven into the very constants that describe the behaviors we see and can measure to a very, very high degree of accuracy. This is as predicted by physical theory and validated over and over and over again.

So my answer is No!

Maybe that's why we do not see real alien space craft circling our planet. It takes too damned long to make any such interstellar journey.

Sorry, Star Trek fans (I am one myself). Warp drive is a fictional device to move the plot forward in a reasonable amount of time. Nothing more.