Journal of Commutative Algebra

Hilbert-Kunz multiplicity of products of ideals

Neil Epstein and Javid Validashti

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We give bounds for Hilbert-Kunz multiplicity of products of two ideals and characterize the equality in terms of the tight closures of the ideals. Connections are drawn with $*$-spread and with ordinary length calculations.

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J. Commut. Algebra, Volume 11, Number 2 (2019), 225-236.

First available in Project Euclid: 24 June 2019

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Zentralblatt MATH identifier

Primary: 13D40: Hilbert-Samuel and Hilbert-Kunz functions; Poincaré series
Secondary: 13A35: Characteristic p methods (Frobenius endomorphism) and reduction to characteristic p; tight closure [See also 13B22] 13H15: Multiplicity theory and related topics [See also 14C17]

Hilbert-Kunz multiplicity tight closure


Epstein, Neil; Validashti, Javid. Hilbert-Kunz multiplicity of products of ideals. J. Commut. Algebra 11 (2019), no. 2, 225--236. doi:10.1216/JCA-2019-11-2-225.

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