Ulrich module

A maximal Cohen-Macaulay module $M$ over a Noetherian local ring $(R,\mathfrak{m},k)$ is Ulrich if $e(M)=\mu(M)$ , where $e(M)$ is the Hilbert-Samuel multiplicity of $M$ and $\mu(M)$ is the minimal number of generators of $M$ . When $M$ is a maximal Cohen-Macaulay module and $\mathfrak{m}$ has a minimal reduction $I$ generated by a system of parameters, $M$ is Ulrich if and only if $\mathfrak{m}M=IM$ .

Title	Ulrich module
Canonical name	UlrichModule
Date of creation	2013-03-22 18:13:38
Last modified on	2013-03-22 18:13:38
Owner	yshen (21076)
Last modified by	yshen (21076)
Numerical id	8
Author	yshen (21076)
Entry type	Definition
Classification	msc 13C14