Department of Mathematics, University of Florida, Gainesville, Florida 32611-8105 ; School of Mathematics, University of East Anglia, Norwich NR4 7TJ, United Kingdom
Abstract:
Let be a finite group of Lie type in characteristic . This paper addresses the problem of describing the irreducible complex (or -adic) representations of that remain absolutely irreducible under the Brauer reduction modulo . An efficient approach to solve this problem for has been elaborated in earlier papers by the authors. In this paper, we use arithmetical properties of character degrees to solve this problem for the groups
provided that . We also prove an asymptotical result, which solves the problem for all finite groups of Lie type over with large enough.