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arXiv · 1612.00154

Representable Chow classes of a product of projective spaces

Federico Castillo·Binglin Li·Naizhen Zhang
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Abstract

Inside a product of projective spaces, we try to understand which Chow classes come from irreducible subvarieties. The answer is closely related to the theory of integer polymatroids. The support of a representable class can be (partially) characterized as some integer point inside a particular polymatroid. If the class is multiplicity-free, we obtain a complete characterization in terms of representable polymatroids. We also generalize some of the results to the case of products of Grassmannians.

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Federico Castillo, Binglin Li, Naizhen Zhang. 2016-12-01. Representable Chow classes of a product of projective spaces. https://arxiv.org/abs/1612.00154

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