Halasi, Z., Maroti, A., Petenyi, F. (2013). Character expansiveness in finite groups. International Journal of Group Theory, 2(2), 9-17. doi: 10.22108/ijgt.2013.1660

Zoltan Halasi; Attila Maroti; Franciska Petenyi. "Character expansiveness in finite groups". International Journal of Group Theory, 2, 2, 2013, 9-17. doi: 10.22108/ijgt.2013.1660

Halasi, Z., Maroti, A., Petenyi, F. (2013). 'Character expansiveness in finite groups', International Journal of Group Theory, 2(2), pp. 9-17. doi: 10.22108/ijgt.2013.1660

Halasi, Z., Maroti, A., Petenyi, F. Character expansiveness in finite groups. International Journal of Group Theory, 2013; 2(2): 9-17. doi: 10.22108/ijgt.2013.1660

We say that a finite group $G$ is conjugacy expansive if for any normal subset $S$ and any conjugacy class $C$ of $G$ the normal set $SC$ consists of at least as many conjugacy classes of $G$ as $S$ does. Halasi, Mar'oti, Sidki, Bezerra have shown that a group is conjugacy expansive if and only if it is a direct product of conjugacy expansive simple or abelian groups. By considering a character analogue of the above, we say that a finite group $G$ is character expansive if for any complex character $\alpha$ and irreducible character $\chi$ of $G$ the character $\alpha \chi$ has at least as many irreducible constituents, counting without multiplicity, as $\alpha$ does. In this paper we take some initial steps in determining character expansive groups.

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