Since we're talking SciFi, one of the most interesting treatments of space-time is Vinge's "A Fire Upon the Deep", in which there are different zone of the gala

Since we're talking SciFi, one of the most interesting treatments of space-time is Vinge's "A Fire Upon the Deep", in which there are different zone of the galaxy that have different space-time characteristics. I find this more interesting than the usual "faster-than-light drive" or "wormhole" sorts of SciFi. (Us engineers are clearly stupid; we actually need to make real things work. SciFi writers just write a high level description, assume that its works as designed, and start the next chapter! :-)