Unification and Models

[rogerl]

So physics is about measurements and following models that can explain stuff even if they don't correlate with reality? For example. General Relativity is believed even if space doesn't really curve. Only spacetime curves but not space. Since space is empty and doesn't have structure. It is not supposed to curve, but in GR.. space and time added together indeed produce curvature (at least in the model) which allegedly explained gravity.

We also have Quantum Field Theory as models of reality too.

But we know we can't unite Quantum Field Theory and General Relativity. Is the fault of this due to our making models that only explain measurements and not focusing on whether it correlates to reality (or how it actually happens in reality)? Perhaps this is related to why we can't unite the two, because physics is not about reality but about models only which explains measurements and hence the problem some models can't be united is because of our own fault?

About Quantum Gravity. Is QG all about quantizing gravity or does it have to do with how quantum objects got coupled to spacetime? I mean. If quantum gravity is solved. Would it explain how quantum objects got coupled to spacetime or would it only explain what goes on below the planck scale?

[_PJ_]

I like to think in a simplified picture, of trying to imagine the "length" of sub-Plankc space.
In Relativity, it is continuous and effectively flat, but in Quantum terms, it has an infinite size, similar to fractals, where the topography of the Quantum foam will always be more(increasingly, due to Uncertainty in fact) 'uneven'.

This is a very simplified instance of how Einstein's gravitational curvature is defeated in Quantum terms.
Conversely, the Quantum foam imtself implies that there is more to the distortion of spacetime than gravitons alone, or at least, that gravitons have such a marked effect on such scales, that they can never be fully predictable.

[mehul ahir]

may it happen that time doent reaches 0 seconed befor reaching t=0 seconed it starts again increasing than no law violates niether einstine law nor law of conservation of energy?