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arXiv · 2006.13514

Algebraic sets defined by the commutator matrix

Zhibek Kadyrsizova·Madi Yerlanov
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Abstract

In this paper we study algebraic sets of pairs of matrices defined by the vanishing of either the diagonal of their commutator matrix or its anti-diagonal. We find a system of parameters for the coordinate rings of these two sets and their intersection and show that they are complete intersections. Moreover, we prove that these algebraic sets are $F$-pure over a field of positive prime characteristic and the algebraic set of pairs of matrices with the zero diagonal commutator is $F$-regular.

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Zhibek Kadyrsizova, Madi Yerlanov. 2020-06-24. Algebraic sets defined by the commutator matrix. https://arxiv.org/abs/2006.13514

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