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arXiv · 1206.6966

Inductive approach to effective b-semiampleness

Enrica Floris
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Abstract

It has been conjectured by Prokhorov and Shokurov that the moduli part in the canonical bundle formula is effectively b-semiample. In this work we reduce this conjecture to the case where the base of the fibration has dimension one. Moreover, in the case where the moduli part M is numerically trivial, we prove the existence of an integer m, that depends only on the middle Betti number of a canonical covering of the fibre, such that mM is linearly equivalent to the trivial bundle.

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Enrica Floris. 2012-06-29. Inductive approach to effective b-semiampleness. https://arxiv.org/abs/1206.6966

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