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arXiv · 1903.01924

Length of Perverse Sheaves on Hyperplane Arrangements

Nero Budur·Yongqiang Liu
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Abstract

In this article we address the length of perverse sheaves arising as direct images of rank one local systems on complements of hyperplane arrangements. In the case of a cone over an essential line arrangement with at most triple points, we provide combinatorial formulas for these lengths. As by-products, we also obtain in this case combinatorial formulas for the intersection cohomology Betti numbers of rank one local systems on the complement with same monodromy around the planes.

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Nero Budur, Yongqiang Liu. 2019-03-05. Length of Perverse Sheaves on Hyperplane Arrangements. https://arxiv.org/abs/1903.01924

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