An Improved Upper Bound for the Perturbation Index

Ton That Quoc Tan

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arXiv · 2609.05299

An Improved Upper Bound for the Perturbation Index

Ton That Quoc Tan

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Abstract

Let $(R,\mathfrak m)$ be a Noetherian local ring and $J$ be an arbitrary ideal of $R$. Suppose that $f_1,\ldots,f_r$ is a $J$-filter regular sequence in $R$ and $I=(f_1,\ldots,f_r)$. In this paper, we establish an improved upper bound for the perturbation index of the associated graded ring $\mathrm{gr}_J(R/I)$, refining the bound obtained by Quy and N. V. Trung.

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Ton That Quoc Tan. 2026-09-04. An Improved Upper Bound for the Perturbation Index. https://arxiv.org/abs/2609.05299

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