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Comment by cevi

Unfortunately no, ZFC isn't good enough to capture arithmetical truth. The problem is that there are nonstandard models of ZFC where every single model of second-order PA within is itself nonstandard. There are even models of ZFC where a certain specific computer program, known as the "universal algorithm" [1], solves the halting problem for all standard Turing machines.

https://jdh.hamkins.org/the-universal-algorithm-a-new-simple...

parent cevi 1 year ago

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