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arXiv · 1809.05755

A Rigid Local System with Monodromy Group 2.J_2

Nicholas M. Katz·Antonio Rojas-León
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Abstract

We exhibit a rigid local system of rank six on the affine line in characteristic $p=5$ whose arithmetic and geometric monodromy groups are the finite group $2.J_2$ ($J_2$ the Hall-Janko sporadic group) in one of its two (Galois-conjugate) irreducible representation of degree six.

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Nicholas M. Katz, Antonio Rojas-León. 2018-09-15. A Rigid Local System with Monodromy Group 2.J_2. https://arxiv.org/abs/1809.05755

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