English

Almost cyclic elements in cross-characteristic representations of finite groups of Lie type

Group Theory 2019-10-22 v2

Abstract

This paper is a significant contribution to a general programme aimed to classify all projective irreducible representations of finite simple groups over an algebraically closed field, in which the image of at least one element is represented by an almost cyclic matrix (that is, a square matrix MM of size nn over a field FF with the property that there exists αF\alpha\in F such that MM is similar to diag(αIdk,M1)diag(\alpha \cdot Id_k, M_1), where M1M_1 is cyclic and 0kn0\leq k\leq n). While a previous paper dealt with the Weil representations of finite classical groups, which play a key role in the general picture, the present paper provides a conclusive answer for all cross-characteristic projective irreducible representations of the finite quasi-simple groups of Lie type and their automorphism groups.

Keywords

Cite

@article{arxiv.1806.07885,
  title  = {Almost cyclic elements in cross-characteristic representations of finite groups of Lie type},
  author = {Lino Di Martino and Marco A. Pellegrini and Alexandre E. Zalesski},
  journal= {arXiv preprint arXiv:1806.07885},
  year   = {2019}
}

Comments

To appear on Journal of Group Theory