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arXiv · 1507.05667

Star Configurations are Set-Theoretic Complete Intersections

Stefan Tohaneanu
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Abstract

Let $\mathcal A\subset\mathbb P^{k-1}$ be a rank $k$ arrangement of $n$ hyperplanes, with the property that any $k$ of the defining linear forms are linearly independent (i.e., $\mathcal A$ is called $k-$generic). We show that for any $j=0,\ldots,k-2$, the subspace arrangement with defining ideal generated by the $(n-j)-$fold products of the defining linear forms of $\mathcal A$ is a set-theoretic complete intersection, which is equivalent to saying that star configurations have this property.

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Stefan Tohaneanu. 2015-07-20. Star Configurations are Set-Theoretic Complete Intersections. https://doi.org/10.1007/s00013-015-0817-7

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