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arXiv · 2308.09680

Number of triple points on complete intersection Calabi-Yau threefolds

Kacper Grzelakowski
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Abstract

We discuss bounds for the number of ordinary triple points on complete intersection Calabi-Yau threefolds in projective spaces and for Calabi-Yau threefolds in weighted projective spaces. In particular, we show that in P5 the intersection of a quadric and a quartic cannot have more than 10 ordinary triple points. We provide examples of complete intersection Calabi-Yau threefolds with multiple triple points. We obtain the exact bound for a sextic hypersurface in P[1 : 1 : 1 : 1 : 2], which is 10. We also discuss Calabi-Yau threefolds that cannot admit triple points.

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Kacper Grzelakowski. 2023-08-18. Number of triple points on complete intersection Calabi-Yau threefolds. https://arxiv.org/abs/2308.09680

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