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arXiv · 1511.01738

Fano 4-folds, flips, and blow-ups of points

Cinzia Casagrande
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Abstract

In this paper we study smooth, complex Fano 4-folds X with large Picard number rho(X), with techniques from birational geometry. Our main result is that if X is isomorphic in codimension one to the blow-up of a smooth projective 4-fold Y at a point, then rho(X) is at most 12. We give examples of such X with Picard number up to 9. The main theme (and tool) is the study of fixed prime divisors in Fano 4-folds, especially in the case rho(X)>6, in which we give some general results of independent interest.

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Cinzia Casagrande. 2017-04-05. Fano 4-folds, flips, and blow-ups of points. https://arxiv.org/abs/1511.01738

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