I have overlooked or downplayed a point in There Will Be Time. Previously, I had reflected that time travelers would be able to move pastward or futureward along the world-line of a slower than light interstellar spaceship - and I think that this or something like it did happen in Edmund Cooper's Seed Of Light which I read many years ago. Poul Anderson presents the idea at least of futureward travel in an STL ship in the concluding chapter of There Will Be Time but also writes:
"'Physicists talk about a mathematical equivalence between traveling into the past and flying faster than light.'" (p. 174)
Thus, although I had thought that the future of There Will Be Time involves a combination of time travel and STL interstellar travel, it is also possible that, in this future, the datum of mutant time travelers enables physicists to conceptualize, then realize, FTL interstellar travel. What might a sequel have been like?
And I said most of this in 2012: see Time Travel And Space Travel.
The future society built by the time travelers is culturally wealthy because it welcomes alien "'...starfarers...'" (p. 175) not only for their material goods but more for:
"'Ideas, arts, experience, insights born on a thousand different worlds, out of a thousand different kinds of being...'" (ibid.)
Maurai society, post-nuclear but pre-time-travel, had developed philosophers and mystics who think, feel, seek meanings and ask challenging questions. However, thought requires subject matter which must come from outside. Thus, the Star Masters civilization synthesizes successive social stages.
5 comments:
Kaor, Paul!
The thought I had was to be skeptical that a truly FTL means of interstellar travel will ever be possible. However, something like the hyperdrive of the Technic Civilization stories might be possible. If I recall correctly the discussion Persis d'Io had with Lord Hauksberg in ENSIGN FLANDRY, the hyperdrive works by using OTHER than the speed of light. A ship instantaneously jumps many times in another dimension and reappears where it's desired to be. So that the Einsteinian speed of light is not violated.
Sean
Kaor, Sean!
Anderson, who had a degree in physics, made this sound plausible, but I don’t believe it’s possible, at least not if relativity is true. According to special relativity, the universe can be equally well described in different reference frames, with the same laws of physics valid in all of them. Thus, an event on Terra and an event on Dennitza can be viewed as happening at the same time and 200 light years apart, or the event on Terra may be viewed as occurring approximately 20 years earlier and 199 light years from Dennitza; the square root of the quantity [x**2 + c**2t**2] is invariant, where **2 means squared, c is the speed of light, and x and t are the separations in time and space.
Thus, if it is possible to use the hyperdrive to travel between the planets in two weeks, one may report the news from Dennitza to Terra before it happens, and cause the Emperor to send an expedition to deal with Aycharaych and the Merseians on Dennitza before they can make trouble, leading to a paradox. So FTL travel and even communication are probably not possible, or if they are, then time travel is, and we have to deal with the paradoxes resulting from that.
Best Regards,
Nicholas
Nicholas,
I have no training in physics or math and cannot understand relativistic equations. The relativity of simultaneity + FTL = time travel?
Paul.
Kaor, Nicholas and Paul!
Nicholas: Many thanks! Trying to wrestle with the problems and paradoxes posed by any kind of "FTL" drive is mind numbing and paradoxical indeed! Just as bad as trying to grapple with the problems posed by time travel.
Yes, a SCIENTIST like Anderson, with his deep knowledge of physics and astronomy, could make the hyperdrive of his Technic stories SEEM plausible. And I remember Anderson writing somewhere in one of his essays that if you plied a physicist with a few stiff drinks (to make him forget about scientific caution!) and then asked him if a FTL drive is possible, the physicist would start talking about the really weird, hairy, and far out fringes of physics, speculating about a real FTL drive.
Paul: I think I first came across the idea that if FTL is possible, then so is time travel near the end of the third of Stirling's three Nantucket books.
Sean
Kaor, Paul!
The short version is that in different reference frames, different events are separated in different ways, and according to relativity, different non-accelerated reference frames are equally valid, and the laws of physics work the same way in all of them. Thus, in one reference frame, two events (two points in space-time) can be simultaneous, and separated by distance in space; in another, they are separated by both space and time, one being earlier than the other. Therefore, if it is possible to travel instantly between them in the first reference frame, it is possible to travel back in time in the second reference frame. You can substitute “faster than light, or with a pseudovelocity achieved through multiple quantum microjumps, as in some of Poul Anderson’s science fiction” for “instantly”, and the conclusion still applies.
Best Regards,
Nicholas
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