>But I'm much more fascinated by the notion that spacecraft (flying
>saucers,etc..) would be impractical for interstellar travel, given the
>inviobility of FTL travel. Not knowing enough to go on about the
>physics involved, my question is more a request for illumination.
Pardon my casual descriptions, but I'm not a physicist.
It's probably more accurate to say that FTL travel is meaningless, rather
than just impossible. As you go faster, the universe gets smaller. To a
photon, the entire universe is just one point. Go faster, and the universe
is imaginary. You have nowhere to come from and nowhere to go.
If, hypothetically, it were possible to get from one point without travelling
(the wormhole concept), it would be trivial to set up grotesque paradoxes.
For example, you "pop" from A to B, where a big bomb is about to go off. You
can set up an observer C who will see you get the before the bomb and get
blown to bits, while D sees you get there after and search the wreckage.
This kind of thing was the basis of a whole bevy of clock paradoxes which
were thought to "disprove" relativity. The way relativity works, however,
everybody always agrees on the sequence of events at a given point. But this
requires that the only way to get from one place to another is by mundane
travel.