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arXiv · 2610.13450

A complex associated to a family of ideals and applications to subspace arrangements

Aldo Conca·Manolis C. Tsakiris
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Abstract

We reprove and generalize a result of Derksen describing the Hilbert polynomial of the vanishing ideal of a transversal subspace arrangement in projective space. When the subspaces have all codimension 2, we describe explicitly the local cohomology modules of the corresponding defining ideal. This is achieved via a complex naturally associated to the subspace arrangement, whose basic properties are also investigated.

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Aldo Conca, Manolis C. Tsakiris. 2026-10-09. A complex associated to a family of ideals and applications to subspace arrangements. https://arxiv.org/abs/2610.13450

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