Approximation Theory and Elementary Submodels

Sean Cox

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arXiv · 2405.19634

Approximation Theory and Elementary Submodels

Sean Cox

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Abstract

\emph{Approximation Theory} uses nicely-behaved subcategories to understand entire categories, just as projective modules are used to approximate arbitrary modules in classical homological algebra. We use set-theoretic \emph{elementary submodel arguments} to give new, short proofs of well-known theorems in approximation theory, sometimes with stronger results.

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BibTeX RIS

Sean Cox. 2024-05-30. Approximation Theory and Elementary Submodels. https://arxiv.org/abs/2405.19634

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