Conjugacy classes and characters for extensions of finite groups

Abstract

Let H be an extension of a finite group Q by a finite group G. Inspired by the results of duality theorems for étale gerbes on orbifolds, the authors describe the number of conjugacy classes of H that map to the same conjugacy class of Q. Furthermore, a generalization of the orthogonality relation between characters of G is proved.

Keywords

Group extensions / Conjugacy classes / Orthogonality of characters

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