Unitarizability of Harish-Chandra bimodules over generalized Weyl and $q$-Weyl algebras

Abstract: Let $\mathcal{A}$ be a generalized Weyl or $q$-Weyl algebra, $M$ be an $\mathcal{A}$-$\overline{\mathcal{A}}$ bimodule. Choosing an automorphism $\rho$ of $\mathcal{A}$ we can define the notion of an invariant Hermitian form: $(au,v)=(u,v\rho(a))$ for all $a\in \mathcal{A}$ and $u,v\in M$. Papers [P. Etingof, D. Klyuev, E. Rains, D. Stryker. Twisted traces and positive forms on quantized Kleinian singularities of type A. SIGMA 17 (2021), 029, 31 pages, arXiv:2009.09437] and [D. Klyuev. Twisted traces and positive forms on generalized q-Weyl algebras. SIGMA 18 (2022), 009, 28 pages, arXiv:2105.12652] obtained a classification of invariant positive definite Hermitian forms in the case when $M=\mathcal{A}=\overline{\mathcal{A}}$, the case of the regular bimodule. We obtain a classification of invariant positive definite forms on $M$ in the case when $\mathcal{A}$ has no finite-dimensional representations.