Complete intersections in spherical varieties

Kiumars Kaveh; A. G. Khovanskii

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arXiv · 1506.03155

Complete intersections in spherical varieties

Kiumars Kaveh·A. G. Khovanskii

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Abstract

Let G be a complex reductive algebraic group. We study complete intersections in a spherical homogeneous space G/H defined by a generic collection of sections from G-invariant linear systems. Whenever nonempty, all such complete intersections are smooth varieties. We compute their arithmetic genus as well as some of their h^{p,0} numbers. The answers are given in terms of the moment polytopes and Newton-Okounkov polytopes associated to G-invariant linear systems. We also give a necessary and sufficient condition on a collection of linear systems so that the corresponding generic complete intersection is nonempty. This criterion applies to arbitrary quasi-projective varieties (i.e. not necessarily spherical homogeneous spaces). When the spherical homogeneous space under consideration is a complex torus (C^*)^n, our results specialize to well-known results from the Newton polyhedra theory and toric varieties.

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BibTeX RIS

Kiumars Kaveh, A. G. Khovanskii. 2015-06-10. Complete intersections in spherical varieties. https://arxiv.org/abs/1506.03155

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