On the cogeneration of cotorsion pairs

Paul C. Eklof; Saharon Shelah; Jan Trlifaj

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On the cogeneration of cotorsion pairs

Paul C. Eklof·Saharon Shelah·Jan Trlifaj

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Abstract

Let R be a Dedekind domain. Enochs' solution of the Flat Cover Conjecture was extended as follows: (*) If C is a cotorsion pair generated by a class of cotorsion modules, then C is cogenerated by a set. We show that (*) is the best result provable in ZFC in case R has a countable spectrum: the Uniformization Principle UP^+ implies that C is not cogenerated by a set whenever C is a cotorsion pair generated by a set which contains a non-cotorsion module.

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BibTeX RIS

Paul C. Eklof, Saharon Shelah, Jan Trlifaj. 2004-05-07. On the cogeneration of cotorsion pairs. https://arxiv.org/abs/math/0405117

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