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arXiv · 2004.04982

A maximally-graded invertible cubic threefold that does not admit a full exceptional collection of line bundles

David Favero·Daniel Kaplan·Tyler L. Kelly
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Abstract

We show that there exists a cubic threefold defined by an invertible polynomial that, when quotiented by the maximal diagonal symmetry group, has a derived category which does not have a full exceptional collection consisting of line bundles. This provides a counterexample to a conjecture of Lekili and Ueda.

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David Favero, Daniel Kaplan, Tyler L. Kelly. 2020-04-10. A maximally-graded invertible cubic threefold that does not admit a full exceptional collection of line bundles. https://arxiv.org/abs/2004.04982

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