There are two basic stances one might take on the metaphysical structure of time: the A-theory and the B-theory. A-theorists contend there is an important, objective distinction between the present and other times. They typically add to this a thesis about time "flowing" from past, to present, to future. B-theorists deny this package -- they think of time as "spread out" the way we ordinarily think of space as spread out. They deny there is a fundamental directionality to time, at least any directionality beyond some times being earlier or later than others in the manifold. B-theorists are often thought to have a special challenge in explaining why we experience an asymmetry in time if none is actually there.Naturally this knocks sciencefictional sparks from the flint of my mind. I think of Herbert's prophet, in Dune Messiah, who is blind, but who can 'see' the world around him by remembering the very detailed visions he had of the then-future, now-present, in the past. Herbert makes no larger philosophical claims for this notion (surprisingly, perhaps, given how crammed with second-hand philosophy the Dune novels are) but I wonder if it mightn't be an illuminating way of thinking about perceptual time?
Or again: 'why do we seem to experience time passing, if in fact we inhabit a directionless manifold?' Taking up the 'if', here, and suggesting an answer to the question: presumably for the same reasons we experience motion in space. Presumably there is a time-gravity, and we are being accelerated (hence the sensation of motion) towards a very massive temporal 'object' located in a particular direction of the manifold. Presumably again there is no upper limit to our absolute 'speed' through time -- unlike space -- although the acceleration is constant and enough to give us a sense of one day passing every day (it must be temporal acceleration, or we wouldn't have the sensation of moving forward at all, of course). But what happens when we collectively arrive at the temporally supermassive object that is drawing us? And what if there were a temporal equivalent to 'c'?
This last notion gives me an idea for a story.