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arXiv · 2402.02305

On the Castelnuovo-Mumford regularity of subspace arrangements

Aldo Conca·Manolis C. Tsakiris
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Abstract

Let $X$ be the union of $n$ generic linear subspaces of codimension $>1$ in $\mathbb{P}^d$. Improving an earlier bound due to Derksen and Sidman, we prove that the Castelnuovo-Mumford regularity of $X$ satisfies $ \operatorname{reg}(X) \le n - [n / (2d-1)]$.

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Aldo Conca, Manolis C. Tsakiris. 2026-06-19. On the Castelnuovo-Mumford regularity of subspace arrangements. https://arxiv.org/abs/2402.02305

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