A Random Walk on the Indecomposable Summands of Tensor Products of Modular Representations of SL2 (Fp)

Eoghan McDowell

Research output: Contribution to journalArticlepeer-review


In this paper we introduce a novel family of Markov chains on the simple representations of SL_2(F_p) in defining characteristic, defined by tensoring with a fixed simple module and choosing an indecomposable non-projective summand. We show these chains are reversible and find their connected components and their stationary distributions. We draw connections between the properties of the chain and the representation theory of SL_2(F_p), emphasising symmetries of the tensor product. We also provide an elementary proof of the decomposition of tensor products of simple SL_2(F_p)-representations.
Original languageEnglish
JournalAlgebras and Representation Theory
Early online date12 Mar 2021
Publication statusE-pub ahead of print - 12 Mar 2021

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