Let M be a manifold with an action of a Lie group G, $\A$ the function algebra on M.
The first problem we consider is to construct a $U_h(\g)$ invariant quantization, $\A_h$, of $\A$, where $U_h(\g)$ is a quantum group corresponding to G.
Let s be a G invariant Poisson bracket on M. The second problem we consider is to construct a $U_h(\g)$ invariant two parameter (double) quantization, $\A_{t,h}$, of $\A$ such that $\A_{t,0}$ is a G invariant quantization of $s$. We call $\A_{t,h}$ a $U_h(\g)$ invariant quantization of the Poisson bracket s.
In the paper we study the cases when G is a simple Lie group and $M$ is the coadjoint representation $\g^*$ of G or a semisimple orbit in this representation.
The paper is founded on the papers: J.Donin, Double quantization on the coadjoint representation of $sl(n)^*$, Czechoslovak J. of Physics, 47 (1997), no 11, 1115-1122, q-alg/9707031, and J.Donin, D.Gurevich, and S.Shnider, Double Quantization on Some Orbits in the Coadjoint Representations of Simple Lie Groups, Com. Math. Phys., 204 (1999), no. 1, 39-60, math/9807159, and contains some additional results.
Let M be a coadjoint semisimple orbit of a simple Lie group G. Let $U_h(\g)$ be a quantum group corresponding to G. We construct a universal family of $U_h(\g)$ invariant quantizations of the sheaf of functions on M and describe all such quantizations. We also describe all two parameter $U_h(\g)$ invariant quantizations on M, which can be considered as $U_h(\g)$ invariant quantizations of the Kirillov-Kostant-Souriau (KKS) Poisson bracket on M. We also consider how those quantizations relate to the natural polarizations of M with respect to the KKS bracket. Using polarizations, we quantize the…
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