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Have there been any recent developments in the attempt to unify the standard model of quantum theory with General Relativity? It appears the no progress has been made recently in string theory or loop quantum gravity.
Recent discussions indicate a stagnation in unifying quantum theory with General Relativity, particularly in the realms of string theory and loop quantum gravity. Participants express skepticism about proving incompleteness in physical theories, contrasting it with Gödel's work in mathematics. The conversation highlights the complexities of reconciling classical logic with non-conventional logics in the context of physical theories. The Bell theorem is mentioned as a potential framework for understanding the limitations of quantum mechanics in relation to general covariance.
PREREQUISITESPhysicists, mathematicians, and researchers interested in theoretical physics, particularly those focused on the unification of quantum mechanics and General Relativity.

What will make you a pessimist?mathman said:I am somewhat more optimistic. Godel was dealing in mathematics. I doubt if you can "prove" incompleteness for physical theories.
This seems like a total non sequitur to me. How do you get from true but not provable propositions in an axiomatic system to propositions that “won’t make sense”?MathematicalPhysicist said:Well a physical theory is constructed with maths, so the mathematics will be incomplete, and the physics won't make sense anyway, it's either inconsistent or incomplete.
Well "making sense" is with regards to classical logic.Nugatory said:This seems like a total non sequitur to me. How do you get from true but not provable propositions in an axiomatic system to propositions that “won’t make sense”?
Godel does not have "true but not provable" propositions. It has unprovable propositions that become axioms as you extend the maths. The axioms are neither true not false. You can accept them as true, or you can accept various negations of them as true. E.g. the unprovable generalized continuum hypothesis may be accepted or rejected according to taste.Nugatory said:This seems like a total non sequitur to me. How do you get from true but not provable propositions in an axiomatic system to propositions that “won’t make sense”?
It could be something like the Bell theorem for local hidden variables in quantum mechanics. The theorem might state that no theory can simultaneously have properties of being (i) quantum, (ii) general covariant and (iii) obeying some additional property that currently everybody takes for granted.mathman said:I am somewhat more optimistic. Godel was dealing in mathematics. I doubt if you can "prove" incompleteness for physical theories.