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arXiv · 2305.18167

Ladder determinantal varieties and their symbolic blowups

Alessandro De Stefani·Jonathan Montaño·Luis Núñez-Betancourt·Lisa Seccia·Matteo Varbaro
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Abstract

In this article we show that the symbolic Rees algebra of a mixed ladder determinantal ideal is strongly $F$-regular. Furthermore, we prove that the symbolic associated graded algebra of a mixed ladder determinantal ideal is $F$-pure. The latter implies that mixed ladder determinantal rings are $F$-pure. We also show that ideals of the poset of minors of a generic matrix give rise to $F$-pure algebras with straightening law.

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Alessandro De Stefani, Jonathan Montaño, Luis Núñez-Betancourt, Lisa Seccia, Matteo Varbaro. 2023-05-29. Ladder determinantal varieties and their symbolic blowups. https://arxiv.org/abs/2305.18167

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