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arXiv · 1710.00462

Local cohomology and Lyubeznik numbers of $F$-pure rings

Alessandro De Stefani·Eloísa Grifo·Luis Núñez-Betancourt
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Abstract

In this article, we study certain local cohomology modules over $F$-pure rings. We give sufficient conditions for the vanishing of some Lyubeznik numbers, derive a formula for computing these invariants when the $F$-pure ring is standard graded and, by its means, we provide some new examples of Lyubeznik tables. We study associated primes of certain Ext-modules, showing that they are all compatible ideals. Finally, we focus on properties that Lyubeznik numbers detect over a globally $F$-split projective variety.

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Alessandro De Stefani, Eloísa Grifo, Luis Núñez-Betancourt. 2017-10-02. Local cohomology and Lyubeznik numbers of $F$-pure rings. https://arxiv.org/abs/1710.00462

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