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GENERALISED GELFAND–GRAEV REPRESENTATIONS IN BAD CHARACTERISTIC ?

Transformation Groups volume 26, pages305–326(2021)Cite this article

Abstract

Let G be a connected reductive algebraic group defined over a finite field with q elements. In the 1980’s, Kawanaka introduced generalised Gelfand–Graev representations of the finite group \( G\left({\mathbbm{F}}_q\right) \), assuming that q is a power of a good prime for G. These representations have turned out to be extremely useful in various contexts. Here we investigate to what extent Kawanaka’s construction can be carried out when we drop the assumptions on q. As a curious by-product, we obtain a new, conjectural characterisation of Lusztig’s concept of special unipotent classes of G in terms of weighted Dynkin diagrams.

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  1. IAZ - Lehrstuhl für Algebra, Universität Stuttgart, Pfaffenwaldring 57, D-70569, Stuttgart, Germany

    MEINOLF GECK

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GECK, M. GENERALISED GELFAND–GRAEV REPRESENTATIONS IN BAD CHARACTERISTIC ?. Transformation Groups 26, 305–326 (2021). https://doi.org/10.1007/s00031-020-09575-3

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