Abstract
We prove that for any non-trivial product-type action α of SU q (n) (0<q<1) on an ITPFI factor N, the relative commutant is isomorphic to the algebra L ∞() of bounded measurable functions on the quantum flag manifold . This is equivalent to the computation of the Poisson boundary of the dual discrete quantum group . The proof relies on a connection between the Poisson integral and the Berezin transform. Our main technical result says that a sequence of Berezin transforms defined by a random walk on the dominant weights of SU(n) converges to the identity on the quantum flag manifold.
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Communicated by Y. Kawahigashi
Supported by JSPS.
Partially supported by the Norwegian Research Council.
Supported by the SUP-program of the Norwegian Research Council.
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Izumi, M., Neshveyev, S. & Tuset, L. Poisson Boundary of the Dual of SU q (n). Commun. Math. Phys. 262, 505–531 (2006). https://doi.org/10.1007/s00220-005-1439-x
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DOI: https://doi.org/10.1007/s00220-005-1439-x