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arXiv · 2311.13510

Jordan correspondence and block distribution of characters

Abstract

We complete the determination of the $\ell$-block distribution of characters for quasi-simple exceptional groups of Lie type up to some minor ambiguities relating to non-uniqueness of Jordan decomposition. For this, we first determine the $\ell$-block distribution for finite reductive groups whose ambient algebraic group defined in characteristic different from $\ell$ has connected centre. As a consequence we derive a compatibility between $\ell$-blocks, $e$-Harish-Chandra series and Jordan decomposition. Further we apply our results to complete the proof of Robinson's conjecture on defects of characters.

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BibTeXRIS

Radha Kessar, Gunter Malle. 2023-11-22. Jordan correspondence and block distribution of characters. https://arxiv.org/abs/2311.13510

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