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arXiv · 2312.01230

On containment of trace ideals in ideals of finite homological dimension

Abstract

Motivated by recent result of P\'erez and R.G. on equality of test ideal of module closure operation and trace ideal, and the well-known result by Smith that parameter test ideal cannot be contained in parameter ideals, we study the obstruction of containment of trace ideals in ideals of finite projective (or injective) dimension. One of our results says that the trace ideal of any big Cohen--Macaulay module over a Gorenstein complete local domain cannot be contained in any ideal of finite projective dimension, thereby generalizing Smith's result in this case. As consequences of our results, we give upper bounds on $\mathfrak m$-adic order of trace ideals of certain modules over local Cohen--Macaulay rings. We also prove analogous results for ideal of entries of maps in a free resolution of modules.

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BibTeXRIS

Souvik Dey, Monalisa Dutta. 2023-12-02. On containment of trace ideals in ideals of finite homological dimension. https://arxiv.org/abs/2312.01230

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