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Irreducible representations of simple algebraic groups in which a unipotent element is represented by a matrix with a single non-trivial Jordan block

  • Donna M. Testerman EMAIL logo und Alexandre E. Zalesski
Veröffentlicht/Copyright: 17. August 2017

Abstract

Let G be a simply connected simple linear algebraic group of exceptional Lie type over an algebraically closed field F of characteristic p0, and let uG be a nonidentity unipotent element. Let ϕ be a non-trivial irreducible representation of G. Then the Jordan normal form of ϕ(u) contains at most one non-trivial block if and only if G is of type G2, u is a regular unipotent element and dimϕ7. Note that the irreducible representations of the simple classical algebraic groups in which a non-trivial unipotent element is represented by a matrix whose Jordan form has a single non-trivial block were determined by I. D. Suprunenko [21].


Communicated by Christopher W. Parker


Award Identifier / Grant number: 200021_146223

Funding statement: The first author was supported in part by Swiss National Science Foundation (grant no. ). A part of this work was carried out with the generous support of the Bernoulli Center, at the Swiss Federal Institute of Technology Lausanne, when the second author participated in the program “Local representation theory and simple groups” (2016).

Acknowledgements

We would like to thank Gunter Malle for reading an earlier version of the paper and also Irina Suprunenko for providing us with precise details of her own work.

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Received: 2017-4-19
Revised: 2017-5-17
Published Online: 2017-8-17
Published in Print: 2018-1-1

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