Ghost center and representations of the diagonal reduction algebra of
arXiv:2203.08068 · doi:10.1016/j.geomphys.2023.104788
Abstract
Reduction algebras are known by many names in the literature, including step algebras, Mickelsson algebras, Zhelobenko algebras, and transvector algebras, to name a few. These algebras, realized by raising and lowering operators, allow for the calculation of Clebsch-Gordan coefficients, branching rules, and intertwining operators; and have connections to extremal equations and dynamical R-matrices in integrable face models. In this paper we continue the study of the diagonal reduction superalgebra of the orthosymplectic Lie superalgebra . We construct a Harish-Chandra homomorphism, Verma modules, and study the Shapovalov form on each Verma module. Using these results, we prove that the ghost center (center plus anti-center) of is generated by two central elements and one anti-central element (analogous to the Scasimir due to Leśniewski for ). As another application, we classify all finite-dimensional irreducible representations of . Lastly, we calculate an infinite-dimensional tensor product decomposition explicitly.
27 pages; updated introduction: references and motivation; readability; comments welcomed!