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arXiv · 2401.12090

Sch\"on complete intersections

Alexander Esterov
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Abstract

A complete intersection $f_1=\cdots=f_k=0$ is sch\"on, if $f_1=\cdots=f_j=0$ defines a sch\"on subvariety of an algebraic torus for every $j\leqslant k$. This class includes nondegenerate complete intersections, critical loci of their coordinate projections, other simplest Thom--Boardman and multiple point strata of such projections, generalized Calabi--Yau complete intersections, equaltions of polynomial optimization, hyperplane arrangement complements, and many other interesting special varieties. We study their Euler characteristics, connectednes, Calabi--Yau-ness, tropicalizations, etc., extending (in part conjecturally) the respective classical results about nondegenerate complete intersections.

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Alexander Esterov. 2024-01-22. Sch\"on complete intersections. https://arxiv.org/abs/2401.12090

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