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TWO NON-VANISHING RESULTS CONCERNING THE ANTI-CANONICAL BUNDLE

Published online by Cambridge University Press:  20 January 2025

NIKLAS MÜLLER*
Affiliation:
Department of Mathematics Universität Duisburg-Essen Thea-Leymann-Strasse 9 45127 Essen Germany

Abstract

Let $(X, \Delta )$ be a klt threefold pair with nef anti-log canonical divisor $-(K_X+\Delta )$. We show that $\kappa (X, -(K_X+\Delta ))\geq 0$. To do so, we prove a more general equivariant non-vanishing result for anti-log canonical bundles, which is valid in any dimension.

Type
Article
Copyright
© The Author(s), 2025. Published by Cambridge University Press on behalf of Foundation Nagoya Mathematical Journal

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Footnotes

While working on this project, the author was supported by the DFG Research Training Group 2553 “Symmetries and Classifying Spaces: Analytic, Arithmetic and Derived”

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