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arXiv · 1804.09127

Birational boundedness of rationally connected Calabi-Yau 3-folds

Weichung Chen·Gabriele Di Cerbo·Jingjun Han·Chen Jiang·Roberto Svaldi
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Abstract

We prove that rationally connected Calabi--Yau 3-folds with kawamata log terminal (klt) singularities form a birationally bounded family, or more generally, rationally connected $3$-folds of $\epsilon$-CY type form a birationally bounded family for $\epsilon>0$. Moreover, we show that the set of $\epsilon$-lc log Calabi--Yau pairs $(X, B)$ with coefficients of $B$ bounded away from zero is log bounded modulo flops. As a consequence, we deduce that rationally connected klt Calabi--Yau $3$-folds with mld bounded away from $1$ are bounded modulo flops.

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Weichung Chen, Gabriele Di Cerbo, Jingjun Han, Chen Jiang, Roberto Svaldi. 2018-04-24. Birational boundedness of rationally connected Calabi-Yau 3-folds. https://doi.org/10.1016/j.aim.2020.107541

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