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arXiv · 2108.07991

An extension of a depth inequality of Auslander

Olgur Celikbas·Uyen Le·Hiroki Matsui
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Abstract

In this paper, we consider a depth inequality of Auslander which holds for finitely generated Tor-rigid modules over commutative Noetherian local rings. We raise the question of whether such a depth inequality can be extended for $n$-Tor-rigid modules, and obtain an affirmative answer for 2-Tor-rigid modules that are generically free. Furthermore, in the appendix, we use Dao's eta function and determine new classes of Tor-rigid modules over hypersurfaces that are quotient of unramified regular local rings.

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Olgur Celikbas, Uyen Le, Hiroki Matsui. 2021-08-18. An extension of a depth inequality of Auslander. https://arxiv.org/abs/2108.07991

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