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arXiv · 1701.05592

Invariants of Cohen-Macaulay rings associated to their canonical ideals

Laura Ghezzi·Shiro Goto·Jooyoun Hong·Wolmer Vasconcelos
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Abstract

The purpose of this paper is to introduce new invariants of Cohen-Macaulay local rings. Our focus is the class of Cohen-Macaulay local rings that admit a canonical ideal. Attached to each such ring R with a canonical ideal C, there are integers--the type of R, the reduction number of C--that provide valuable metrics to express the deviation of R from being a Gorenstein ring. We enlarge this list with other integers--the roots of R and several canonical degrees. The latter are multiplicity based functions of the Rees algebra of C.

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Laura Ghezzi, Shiro Goto, Jooyoun Hong, Wolmer Vasconcelos. 2017-01-19. Invariants of Cohen-Macaulay rings associated to their canonical ideals. https://arxiv.org/abs/1701.05592

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