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arXiv · 1310.5315

Birational Mori fiber structures of Q-Fano 3-fold weighted complete intersections

Takuzo Okada
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Abstract

In this paper we consider Q-Fano 3-fold weighted complete intersections of codimension 2 in the 85 families listed in the Iano-Fletcher's list and determine which cycle is a maximal center or not. For each maximal center, we construct either a birational involution which untwists the maximal singularity or a Sarkisov link centered at the cycle to an another explicitly described Mori fiber space. As a consequence, 19 families are proved to be birationally rigid and the remaining 66 families are proved to be birationally nonrigid.

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Takuzo Okada. 2014-02-05. Birational Mori fiber structures of Q-Fano 3-fold weighted complete intersections. https://arxiv.org/abs/1310.5315

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