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arXiv · 1307.3208

Local positivity of line bundles on smooth toric varieties and Cayley polytopes

Anders Lundman
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Abstract

For any non-negative integer $k$ the $k$-th osculating dimension at a given point $x$ of a variety $X$ embedded in projective space gives a measure of the local positivity of order $k$ at that point. In this paper we show that a smooth toric embedding having maximal $k$-th osculating dimension, but not maximal $(k+1)$-th osculating dimension, at every point is associated to a Cayley polytope of order $k$. This result generalises an earlier characterisation by David Perkinson. In addition we prove that the above assumptions are equivalent to requiring that the Seshadri constant is exactly $k$ at every point of $X$, generalising a result of Atsushi Ito.

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Anders Lundman. 2013-07-11. Local positivity of line bundles on smooth toric varieties and Cayley polytopes. https://arxiv.org/abs/1307.3208

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