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arXiv · 1512.08119

Covers, envelopes, and cotorsion theories in locally presentable abelian categories and contramodule categories

Leonid Positselski·Jiri Rosicky
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Abstract

We prove general results about completeness of cotorsion theories and existence of covers and envelopes in locally presentable abelian categories, extending the well-established theory for module categories and Grothendieck categories. These results are then applied to the categories of contramodules over topological rings, which provide examples and counterexamples.

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Leonid Positselski, Jiri Rosicky. 2015-12-26. Covers, envelopes, and cotorsion theories in locally presentable abelian categories and contramodule categories. https://doi.org/10.1016/j.jalgebra.2017.03.029

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