Algebra & Number Theory

Block components of the Lie module for the symmetric group

Roger Bryant and Karin Erdmann

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Let F be a field of prime characteristic p and let B be a nonprincipal block of the group algebra FSr of the symmetric group Sr. The block component Lie(r)B of the Lie module Lie(r) is projective, by a result of Erdmann and Tan, although Lie(r) itself is projective only when pr. Write r=pmk, where pk, and let Sk be the diagonal of a Young subgroup of Sr isomorphic to Sk××Sk. We show that pmLie(r)B(Lie(k)SkSr)B. Hence we obtain a formula for the multiplicities of the projective indecomposable modules in a direct sum decomposition of Lie(r)B. Corresponding results are obtained, when F is infinite, for the r-th Lie power Lr(E) of the natural module E for the general linear group GLn(F).

Article information

Algebra Number Theory, Volume 6, Number 4 (2012), 781-795.

Received: 10 March 2011
Revised: 8 June 2011
Accepted: 6 July 2011
First available in Project Euclid: 20 December 2017

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Mathematical Reviews number (MathSciNet)

Zentralblatt MATH identifier

Primary: 20C30: Representations of finite symmetric groups
Secondary: 20G43: Schur and $q$-Schur algebras 20C20: Modular representations and characters

Lie module symmetric group Lie power Schur algebra block


Bryant, Roger; Erdmann, Karin. Block components of the Lie module for the symmetric group. Algebra Number Theory 6 (2012), no. 4, 781--795. doi:10.2140/ant.2012.6.781.

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