>H Re: Deep time and shallow time

Eugene Leitl (eugene.leitl@lrz.uni-muenchen.de)
Thu, 27 May 1999 12:36:03 -0700 (PDT)

Anders Sandberg writes:
> Transhuman Mailing List
> I like Eugene's ambition of a >HTS, but I think we need to integrate a


> space standard too. After all, we will be dealing with relativistic

Agree very much. I just couldn't think of any really global standard. Using pulsars as timing sources (with compensation for slowdown) for a kind of a galactic time-of-flight GPS is the best I can come up with. Unfortunately, the slowdown constant isn't accurate enough to measure short time spans, and most pulsars are directed. One should record as many of them as possible, a nice analogy to GPS satellite coverage.

> stuff and simultanity will becomre tricky (one could set up some kind
> of "mean universal hyperbolic time" based on the "flattest" spacelike
> slices we can foliate the universe with, but the precision will be
> troublesome).

True, but whoever goes skidding around a singularity will know to readjust his clock when he comes back by synching it with those left behind. Unfortunately, there are no simple sensors directly measuring spacetime curvature...

> Maybe one could do something exactly corresponding to the time format
> to measure space, but the coordinate system will be tough. The
> topology censorship conjecture might make spacetime a bit more boring
> that we have hoped, but it is still bendy and tricky. Some way of
> translating local maps into an atlas? This sounds like an area where
> differential geometry and computational geometry could come in handy.