A ug 2 00 8 Formulas of F - thresholds and F - jumping coefficients on toric rings ∗
نویسنده
چکیده
Mustaţǎ, Takagi and Watanabe define F-thresholds, which are invariants of a pair of ideals in a ring of characteristic p > 0. In their paper, it is proved that F-thresholds are equal to jumping numbers of test ideals on regular local rings. In this note, we give formulas of F-thresholds and F-jumping coefficients on toric rings. By these formulas, we prove that there exists an inequality between F-jumping coefficients and F-thresholds. In particular, we observe a comparison between F-pure thresholds and F-thresholds in some cases. As applications, we give a characterization of regularity for toric rings defined by simplicial cones, and we prove the rationality of F-thresholds in some cases.
منابع مشابه
Se p 20 07 Formulas of F - thresholds and F - jumping coefficients on toric rings ∗
F-thresholds are defined by Mustaţǎ, Takagi and Watanabe, which are invariants of the pair of ideals on rings of characteristic p > 0. In their paper, it is proved F-thresholds equal to jumping numbers for the test ideal on regular local rings. In this note, we give formulas of F-thresholds and F-jumping coefficients on toric rings. We prove that there exists an inequality between F-jumping coe...
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