Spin Representations of Finite Coxeter Groups and Generalisations of Saxl's Conjecture

Abstract

This paper presents a natural generalisation of Saxl conjecture from a Lie-theoretical perspective, which is verified for the exceptional types. For classical types, progress is made using spin representations, revealing connections to certain tensor product decomposition problems in symmetric groups. We provide an alternative uniform description of the cuspidal family (in the sense of Lusztig) through spin representations, offering an equivalent conjecture formulation. Additionally, we generalise Saxl conjecture to finite Coxeter groups and prove it for the non-crystallographic cases.