Earlier quoted context omitted.
Theoretically it's impossible to travel through space at or more than speed of light. But space itself can move faster than light speed, and a warp drive would help something similar that you mentioned. That is possible theoretically. But the amount of energy or mass it needs is very high and no current technology (or in foreseeable future) can achieve it. So FTL remains a dream. My hunch based on nothing is that we…
Yeah the only energy source that can produce enough energy to power an Alcubierre drive (warp drive) that humanity has ever even conceived is a matter-antimatter reactor. But we don’t even fully understand matter, much less antimatter, and are pretty far from that. 2250 at the earliest is not an unreasonable estimate.
As antimatter is as powerful as one can get, it not being powerful enough is a good reason to think it's not going to work.