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The rationality of the Hilbert-Kunz multiplicity in graded dimension two

Holger Brenner
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Abstract

We show that the Hilbert-Kunz multiplicity is a rational number for an R_+-primary homogeneous ideal I=(f_1, ..., f_n) in a two-dimensional graded domain R of finite type over an algebraically closed field of positive characteristic. Moreover we give a formula for the Hilbert-Kunz multiplicity in terms of certain rational numbers coming from the strong Harder-Narasimhan filtration of the syzygy bundle Syz(f_1, . . ., f_n) on the projective curve Y = Proj R.

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Holger Brenner. 2005-07-07. The rationality of the Hilbert-Kunz multiplicity in graded dimension two. https://arxiv.org/abs/math/0402180

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