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Degree bounds for generators of cohomology modules and Castelnuovo-Mumford regularity

Published online by Cambridge University Press:  22 January 2016

Uwe Nagel
Affiliation:
Fachbereich Mathematik und Informatik Universität-Gesamthochschule Paderborn, D - 33095 Paderborn, Germany, uwen@uni-paderborn.de
Peter Schenzel
Affiliation:
Fachbereich Mathematik und Informatik Martin-Luther-Universität, Halle-Wittenberg, D - 06 099 Halle, Germany, schenzel@mathematik.uni-halle.de
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Abstract.

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By extending Mumford’s result on the generating by global sections there are estimates on the degree for generators of local cohomology modules. These arguments provide bounds on the Castelnuovo-Mumford regularity, in particular for Cohen-Macaulay varieties. As an application they imply a few more cases of varieties that satisfy a conjecture posed by Eisenbud and Gôto.

Type
Research Article
Copyright
Copyright © Editorial Board of Nagoya Mathematical Journal 1998

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