Hecke monoids, their homomorphisms and parabolicity

Arkady Berenstein; Jacob Greenstein; Jian-Rong Li

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arXiv · 2605.09761

Hecke monoids, their homomorphisms and parabolicity

Arkady Berenstein·Jacob Greenstein·Jian-Rong Li

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Abstract

We study homomorphisms of Hecke monoids, notably parabolic homomorphisms, which map parabolic elements to parabolic elements, and injective ones. The importance of the first class stems from the fact that parabolic elements form a rather mysterious submonoid of the Hecke monoid, and we found a plethora of parabolic homomorphisms. Concerning injective ones, as a first step towards their classification, we classified all locally injective connected homomorphisms between Hecke monoids of classical types and expect all of them to be injective. As a surprising byproduct of our study of parabolic and injective homomorphisms we described, to some extent, all homomorphisms between Hecke monoids.

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BibTeX RIS

Arkady Berenstein, Jacob Greenstein, Jian-Rong Li. 2026-05-10. Hecke monoids, their homomorphisms and parabolicity. https://arxiv.org/abs/2605.09761

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