Irreducible Specht modules for Hecke algebras of type A

Let F be a field, n a non-negative integer. lambda a partition of n and S-lambda the corresponding Specht module for the Iwahori-Hecke algebra H-F.q(E-n). James and Mathas conjecture a necessary and sufficient condition on lambda for S-lambda to be irreducible. We prove the sufficiency of this condition in the case where F has infinite characteristic and also in the case where q = 1. (c) 2004 Elsevier Inc. All rights reserved.