Fused Hecke algebra and one-boundary algebras
arXiv:2306.10937 · doi:10.2140/pjm.2024.328.77
Abstract
This paper gives an algebraic presentation of the fused Hecke algebra which describes the centraliser of tensor products of the -representation labelled by a one-row partition of any size with vector representations. It is obtained through a detailed study of a new algebra that we call the symmetric one-boundary Hecke algebra. In particular, we prove that the symmetric one-boundary Hecke algebra is free over a ring of Laurent polynomials in three variables and we provide a basis indexed by a certain subset of signed permutations. We show how the symmetric one-boundary Hecke algebra admits the one-boundary Temperley-Lieb algebra as a quotient, and we also describe a basis of this latter algebra combinatorially in terms of signed permutations with avoiding patterns. The quotients corresponding to any value of in (the Temperley-Lieb one corresponds to ) are also introduced. Finally, we obtain the fused Hecke algebra, and in turn the centralisers for any value of , by specialising and quotienting the symmetric one-boundary Hecke algebra. In particular, this generalises to the Hecke case the description of the so-called boundary seam algebra, which is then obtained (taking ) as a quotient of the fused Hecke algebra.
35 pages