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arXiv · 1801.02970

Tree modules and limits of the approximation theory

Jan Trlifaj
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Abstract

In this expository paper, we present a construction of tree modules and combine it with (infinite dimensional) tilting theory and relative Mittag-Leffler conditions in order to explore limits of the approximation theory of modules. We also present a recent generalization of this construction due to Saroch which applies to factorization properties of maps, and yields a solution of an old problem by Auslander concerning existence of almost split sequences.

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BibTeXRIS

Jan Trlifaj. 2018-01-09. Tree modules and limits of the approximation theory. https://doi.org/10.1090/conm%2F716%2F14430

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