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arXiv · 1009.5036

Towards the Classification of Weak Fano Threefolds with \rho = 2

Joseph W. Cutrone·Nicholas A. Marshburn
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Abstract

In this paper, we provide examples of Sarkisov links of type II between complex projective Fano threefolds $X$ with $\rho(X) = 1$. To show examples of these links, we study smooth weak Fano threefolds with extremal rays of type $E$. We further assume that the pluri-anticanonical morphism contracts only a finite number of curves. We numerically classify smooth weak Fano threefolds with $\rho(X) = 2$ having an extremal ray of type $E$ both before and after a flop as well as prove the existence of some of these numerical cases.

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BibTeXRIS

Joseph W. Cutrone, Nicholas A. Marshburn. 2010-09-25. Towards the Classification of Weak Fano Threefolds with \rho = 2. https://arxiv.org/abs/1009.5036

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