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arXiv · 1709.10162

On global Okounkov bodies of spherical varieties

Guido Pezzini·Henrik Seppänen
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Abstract

We define and study the global Okounkov moment cone of a projective spherical variety X, generalizing both the global Okounkov body and the moment body of X defined by Kaveh and Khovanskii. Under mild assumptions on X we show that the global Okounkov moment cone of X is rational polyhedral. As a consequence, also the global Okounkov body of X, with respect to a particular valuation, is rational polyhedral.

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Guido Pezzini, Henrik Seppänen. 2017-09-28. On global Okounkov bodies of spherical varieties. https://arxiv.org/abs/1709.10162

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