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arXiv · 2411.03167

Tight closure of products and F-rational singularities

Alessandro De Stefani·Ilya Smirnov
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Abstract

We prove a characterization of F-rationality in terms of tight closure of products of parameter ideals. Our results are inspired by the theory of complete ideals for surfaces and, in particular, the fundamental results of Lipman-Teissier and Cutkosky characterizing rational surface singularities in terms of products of complete ideals, but are valid also in higher dimensions.

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Alessandro De Stefani, Ilya Smirnov. 2024-11-05. Tight closure of products and F-rational singularities. https://arxiv.org/abs/2411.03167

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