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arXiv · 1804.05648

A negative answer to a question of Aschbacher

Robert A. Wilson
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Abstract

We give infinitely many examples to show that even for simple groups $G$ it is possible for the lattice of overgroups of a subgroup $H$ to be the Boolean lattice of rank $2$, in such a way that the two maximal overgroups of $H$ are conjugate in $G$. This answers negatively a question posed by Aschbacher.

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Robert A. Wilson. 2018-04-16. A negative answer to a question of Aschbacher. https://arxiv.org/abs/1804.05648

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