Large maximal subgroups of almost simple classical groups

Abstract

A proper subgroup \(H\) of a finite group \(G\) is called large if \(|H|^3 \ge |G|\). This paper characterises all the large maximal subgroups of almost simple groups whose socle is a finite simple classical group. For such a socle \(G_0\) and a core-free subgroup \(H_0\), define \(\mathcal{Q}(G_0,H_0)\) as the set of almost simple groups \(G\) with socle \(G_0\) that have a large maximal subgroup \(H\) satisfying \(H_0 = H \cap G_0\). We establish necessary and sufficient conditions on the pair $(G_0,H_0)$ for the set \(\mathcal{Q}(G_0,H_0)\) to be nonempty.