The Hanf numbers of stationary logic. II. Comparison with other logics

Saharon Shelah

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arXiv · math/9201243

The Hanf numbers of stationary logic. II. Comparison with other logics

Saharon Shelah

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Abstract

We show that the ordering of the Hanf number of L_{omega, omega}(wo) (well ordering), L^c_{omega, omega} (quantification on countable sets), L_{omega, omega}(aa) (stationary logic) and second order logic, have no more restraints provable in ZFC than previously known (those independence proofs assume CON(ZFC) only). We also get results on corresponding logics for L_{lambda, mu} .

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Saharon Shelah. 1991-01-15. The Hanf numbers of stationary logic. II. Comparison with other logics. https://arxiv.org/abs/math/9201243

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