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A reduction map for nef line bundles

Thomas Bauer·Frederic Campana·Thomas Eckl·Stefan Kebekus·Thomas Peternell·Slawomir Rams·Tomasz Szemberg·Lorenz Wotzlaw
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Abstract

In a recent preprint, H. Tsuji gave a number of interesting assertions on the structure of pseudo-effective line bundles on projective manifolds. In particular, he postulated the existence of an almost-holomorphic "reduction map", whose fibers are maximal subvarieties on which the line bundle is numerically trivial. The purpose of this note is to give a simple, algebraic proof of the existence of a reduction map in the case where the line bundle is nef.

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Thomas Bauer, Frederic Campana, Thomas Eckl, Stefan Kebekus, Thomas Peternell, Slawomir Rams, Tomasz Szemberg, Lorenz Wotzlaw. 2001-06-18. A reduction map for nef line bundles. https://arxiv.org/abs/math/0106147

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