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arXiv · 2103.03071

Some Singular Lex-Segments

Andrew P. Staal
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Abstract

We study the component structures of some standard-graded Hilbert schemes closely related to a Hilbert scheme of curves studied by Gotzmann. In particular, we encounter examples of singular lex-segment points lying on two and three irreducible components. We find further singular lex-segment points at nearby Hilbert schemes. We conclude by showing that the analogous example at the Hilbert scheme of twisted cubics also has a singular lex-segment point.

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Andrew P. Staal. 2021-03-04. Some Singular Lex-Segments. https://arxiv.org/abs/2103.03071

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