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arXiv · 1512.00049

A note on the growth of regularity with respect to Frobenius

Wenliang Zhang
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Abstract

Let $R=k[x_1,\dots,x_n]/I$ be a standard graded $k$-algebra where $k$ is a field of prime characteristic and let $J$ be a homogeneous ideal in $R$. Denote $(x_1,\dots,x_n)$ by $\mathfrak{m}$. We prove that there is a constant $C$ (independent of $e$) such that the regularity of $H^s_{\mathfrak{m}}(R/J^{[p^e]})$ is bounded above by $Cp^e$ for all $e\geq 1$ and all integers $s$ such that $s+1$ is at least the dimension of the locus where $R/J$ doesn't have finite projective dimension.

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Wenliang Zhang. 2015-11-30. A note on the growth of regularity with respect to Frobenius. https://arxiv.org/abs/1512.00049

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