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Mixed ladder determinantal varieties from two-sided ladders

Elisa Gorla
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Abstract

We study the family of ideals defined by mixed size minors of two-sided ladders of indeterminates. We compute their Groebner bases with respect to a skew-diagonal monomial order, then we use them to compute the height of the ideals. We show that these ideals correspond to a family of irreducible projective varieties, that we call mixed ladder determinantal varieties. We show that these varieties are arithmetically Cohen-Macaulay. We characterize the arithmetically Gorenstein ones, among those that satisfy a technical condition. Our main result consists in proving that mixed ladder determinantal varieties belong to the same G-biliaison class of a linear variety.

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Elisa Gorla. 2006-04-21. Mixed ladder determinantal varieties from two-sided ladders. https://arxiv.org/abs/math/0510529

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