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arXiv · 2106.04818

Restrictions of characters in p-solvable groups

Damiano Rossi·Benjamin Sambale
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Abstract

Let G be a p-solvable group, P a p-subgroup and chi in Irr(G) such that chi(1)_p \ge |G:P|_p. We prove that the restriction chi_P is a sum of characters induced from subgroups Q\le P such that chi(1)_p=|G:Q|_p. This generalizes previous results by Giannelli--Navarro and Giannelli--Sambale on the number of linear constituents of chi_P. Although this statement does not hold for arbitrary groups, we conjecture a weaker version which can be seen as an extension of Brauer--Nesbitt's theorem on characters of p-defect zero. It also extends a conjecture of Wilde.

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Damiano Rossi, Benjamin Sambale. 2021-07-22. Restrictions of characters in p-solvable groups. https://arxiv.org/abs/2106.04818

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