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A sharp bound for the Castelnuovo-Mumford regularity of subspace arrangements

Harm Derksen·Jessica Sidman
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Abstract

We show that the ideal of an arrangement of d linear subspaces of projective space is d-regular in the sense of Castelnuovo and Mumford, answering a question of B. Sturmfels. In particular this implies that the ideal of an arrangement of d subspaces is generated in degrees less than or equal to d.

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Harm Derksen, Jessica Sidman. 2001-09-05. A sharp bound for the Castelnuovo-Mumford regularity of subspace arrangements. https://arxiv.org/abs/math/0109035

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