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arXiv · 2308.14208

Castelnuovo-Mumford regularity for $321$-avoiding Kazhdan-Lusztig varieties

Colleen Robichaux
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Abstract

We prove the Castelnuovo--Mumford regularity of 321-avoiding Kazhdan--Lusztig varieties can be computed combinatorially in terms of $K$-theoretic skew excited Young diagrams. We present an algorithm which gives a lower bound for this regularity and describe a setting in which this algorithm provides precise regularity computations. This algorithm specializes to compute the regularity of all two-sided mixed ladder determinantal varieties.

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Colleen Robichaux. 2025-09-11. Castelnuovo-Mumford regularity for $321$-avoiding Kazhdan-Lusztig varieties. https://arxiv.org/abs/2308.14208

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