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arXiv · 1601.01387

Quasi-cotilting modules and torsion-free classes

Peiyu Zhang·Jiaqun Wei
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Abstract

We prove that all quasi-cotilting modules are pure-injective and cofinendo. It follows that the class CogenM is always a covering class whenever M is a quasi-cotilting module. Some characterizations of quasi-cotilting modules are given. As a main result, we prove that there is a bijective correspondence between the equivalent classes of quasi-cotilting modules and torsion-free covering classes.

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Peiyu Zhang, Jiaqun Wei. 2016-01-07. Quasi-cotilting modules and torsion-free classes. https://arxiv.org/abs/1601.01387

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