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On the general elephant conjecture for Mori conic bundles

Yuri G Prokhorov
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Abstract

Let $f:X\to S$ be an extremal contraction from a threefolds with terminal singularities onto a surface (so called Mori conic bundle). We study some particular cases of such contractions: quotients of usual conic bundles and index two contractions. Assuming Reid's general elephants conjecture we also obtain a rough classification. We present many examples.

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Yuri G Prokhorov. 1996-08-05. On the general elephant conjecture for Mori conic bundles. https://arxiv.org/abs/alg-geom/9608007

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