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 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).
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.
Anders Sandberg Towards Ascension! firstname.lastname@example.org http://www.nada.kth.se/~asa/GCS/M/S/O d++ -p+ c++++ !l u+ e++ m++ s+/+ n--- h+/* f+ g+ w++ t+ r+ !y