Abstract
We describe the generalized Casimir operators and their actions on the positive representations \({\mathcal{P}_\lambda}\) of the modular double of split real quantum groups \({\mathcal{U}_{q\tilde{q}}(\mathfrak{g}_\mathbb{R})}\). We introduce the notion of virtual highest and lowest weights, and show that the central characters admit positive values for all parameters \({\lambda}\). We show that their image defines a semi-algebraic region bounded by real points of the discriminant variety independent of q, and we discuss explicit examples in the lower rank cases.
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Communicated by N. Reshetikhin
Dedicated to the memory of my grandfather N. Y. Wong (1926–2015)
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Ip, I.C.H. Positive Casimir and Central Characters of Split Real Quantum Groups. Commun. Math. Phys. 344, 857–888 (2016). https://doi.org/10.1007/s00220-016-2639-2
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DOI: https://doi.org/10.1007/s00220-016-2639-2