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arXiv · 2007.06208

Intersection cohomology of pure sheaf spaces using Kirwan's desingularization

Kiryong Chung·Youngho Yoon
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Abstract

Let $\mathbf{M}_n$ be the Simpson compactification of twisted ideal sheaves $\mathcal{I}_{L,Q}(1)$ where $Q$ is a rank $4$ quardric hypersurface in $\mathbb{P}^n$ and $L$ is a linear subspace of dimension $n-2$. This paper calculates the intersection Poincar\'e polynomial of $\mathbf{M}_n$ using Kirwan's desingularization method. We obtain the intersection Poincar\'e polynomial of the moduli space for one-dimensional sheaves on del Pezzo surfaces of degree $\geq 8$ by considering wall-crossings of stable pairs and complexes.

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Kiryong Chung, Youngho Yoon. 2020-07-13. Intersection cohomology of pure sheaf spaces using Kirwan's desingularization. https://doi.org/10.1016/j.geomphys.2020.103992

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