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arXiv · 1310.8505

Minkowski decomposition and generators of the moving cone for toric varieties

Piotr Pokora·David Schmitz·Stefano Urbinati
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Abstract

We prove that for smooth projective toric varieties, the Okounkov body of a $T$-invariant pseudo-effective divisor with respect to a $T$-invariant flag decomposes as a finite Minkowski sum of indecomposable polytopes. We prove that these indecomposable polytopes form a Minkowski base and that they correspond to the rays in the secondary fan. Moreover, we present an algorithm to find the Minkowski base.

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Piotr Pokora, David Schmitz, Stefano Urbinati. 2013-10-31. Minkowski decomposition and generators of the moving cone for toric varieties. https://doi.org/10.1093/qmath%2Fhav025

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