PorpoiseSeeker

I suppose the best we can do is apply the cosmological principle (what's here is there) and speculate that what is outside our light cone must be like what we can see. As Widdekind suggests, we can't prove anything we can't measure and observe. In Lee Smolin's Three Roads to Quantum Gravity, he suggests that Topos theory offers mathematical tools to express partial or incomplete knowledge of the sort we seem to discuss here. The longer we wait, the more of the universe our light cone intercepts. Your light cone and mine can intercept different parts of the universe. But you and I can enter into an "honest" relationship (Smolin's words) and each learn more about the universe that we could know on our own. The tool (as far as I can tell) is called Adjointness (see Goldblatt, Topoi, around p430). It is a challenge to get one's head around being an observer of the universe from inside while being a component or product of that universe. The classical separation of observer and observed does not apply. Topos seems to provide tools that don't fall prey to self-reference paradoxes and incompleteness problems. Is there a forum discussion for this topic?

Lee Smolin's Three Roads to Quantum Gravity suggests that both Quantum Loop Gravity and String Theories require discrete time. No danger of experimental verification of any of these speculations any time soon of course. But the quest is a noble one.