On Thompson Problem

Abstract

In 1987, the second author of this paper reported his conjecture, all finite simple groups $S$ can be characterized uniformly using the order of $S$ and the set of element orders in $S$, to Prof. J. G. Thompson. In their communications, Thompson posed his problem about the judgment of solvability of finite groups $G$. In this paper we give a positive answer for Thompson's problem if the prime graph of $G$ is not connection.