Infinity

[Mr Greene]

At this point we're in danger of wading into the debate of Quantum Loop Gravity and the various String Theories.
Slightly arcane for a biologist come accountant, but the discussion seems to be progressing, albeit without any experimental data on the horizon.

Point is that these scientific models, even if they are inaccurate, are naturalistic explanations for reality.  You can, for instance, believe that stars and planets move because there are angels or other invisible beings that are pushing them, but as such a proposition is not testable, falsifiable and leads to no predictions whatsoever, it competes with a limitless set of such hypotheticals.  Like religion, such faith-based claims are themselves drawn from an infinitet set.

Of course as Theoretical Physics they are purely mathmatical models with no testable hypothesis, so some question if they are scientific at all.
But as it stands we seem to have choice of granular spacetime, foamy spacetime or infinitely twisted spacetime.