In Term 1 seminars are held on Tuesdays at 15:00 on Zoom. In Term 2 seminars will be held on Mondays at 17:00 in B3.02 and via MSTeams.
Organisers: Dmitriy Rumynin, Adam Thomas.
16th November: Lucia Morotti (Hannover University).
Title: Decomposition of spin representations of symmetric groups in characteristic 2
Abstract: Any representation of a double cover of a symmetric group can also be viewed as a representation of Sn when reduced to characteristic 2. However not much is known about the corresponding decomposition matrices. For example, while decomposition numbers of Specht modules indexed by 2-parts partitions are known, the decomposition numbers of spin irreducible modules indexed by 2-parts partitions are still mostly unknown, with in most cases only multiplicities of maximal composition factors (under a certain ordering of the modular irreducible representations) being known.
In this talk I will characterise irreducible representations that appear when reducing 2-parts spin representations to characteristic 2 and describe part of the corresponding rows of the decomposition matrices.
30th November: Dávid Szabó (Rényi Institute, Budapest).
Title: Class 2 nilpotent and twisted Heisenberg groups
7th December: Barbara Baumeister (Bielefeld University).
14th December: Ralf Koehl (Giessen University).
17th January: Dave Benson (Aberdeen)
24th January: Vincent Knibbeler (Loughborough)
31st January: Leonid Positselski (Czech Academy of Sciences)
7th February: Nick Gill (Open University)