The simple $\mathscr{B}_{\psi}$-groups

Abstract

In a finite group $ G $, $ \psi(G) $ denotes the sum of element orders of $ G $. A finite group $ G $ is said to be a $\mathscr{B}_{\psi}$-group if $ \psi(H) < |G| $ for any proper subgroup $ H $ of $ G $. In \cite{Lazorec} Lazorec asked: "what can be said about the $\mathscr{B}_{\psi}$ property of the finite simple groups $ \operatorname{PSL}(2, q) $?" In this paper, we answer this question for the case of not only the finite simple groups $ \operatorname{PSL}(2, q) $ but also all other finite simple groups. We show that if $ S $ is a finite simple group, such that $ S \neq Alt(n) $ for any $ n \geq 14 $, then $S$ is a $\mathscr{B}_{\psi}$-group.