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arXiv · 0705.1210

F-thresholds of hypersurfaces

Manuel Blickle·Mircea Mustaţǎ·Karen Smith
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Abstract

We continue our study of F-thresholds begun in math/0607660 by an in depth analysis of the hypersurface case. We use the D--module theoretic description of generalized test ideals which allows us to show that in any F--finite regular ring the F-thresholds of hypersurfaces are discrete and rational (in math/0607660 the finite type over a field case was shown for arbitrary ideals). Furthermore we show that any limit of F-pure thresholds of principal ideals in bouneded dimension is again an F-pure-threshold, hence in particular the limit is rational. The study of the set of F-pure-thresholds leads to natural analogs of conjectures of Shokurov and Kollár (for log canonical thresholds) in the case of F-pure-thresholds.

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Manuel Blickle, Mircea Mustaţǎ, Karen Smith. 2008-01-10. F-thresholds of hypersurfaces. https://arxiv.org/abs/0705.1210

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