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arXiv · 2604.20970

$E_6$-local systems from cubic threefolds

Thomas Krämer·Daniel Litt·Marco Maculan
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Abstract

We produce infinitely many local systems on (level covers of) the moduli space of smooth cubic threefolds, with algebraic monodromy group equal to the exceptional group $E_6$. These local systems arise in the middle cohomology of abelian \'etale covers of the Fano scheme parametrizing lines in the universal cubic threefold.

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Thomas Krämer, Daniel Litt, Marco Maculan. 2026-04-22. $E_6$-local systems from cubic threefolds. https://arxiv.org/abs/2604.20970

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