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Explicit Hilbert spaces for certain unipotent representations III

Alexander Dvorsky·Siddhartha Sahi
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Abstract

We consider the groups G which arise from real semisimple Jordan algebras via the Tits-Koecher-Kantor construction. Such a G is characterized by the fact that it admits a parabolic subgroup P=LN which is conjugate to its opposite, and for which the nilradical N is abelian. In this situation, the Levi component L has a finite number of orbits on N; and each orbit carries a measure which transforms by a character under L. By Mackey theory the space of L2-functions on each orbit carries a natural irreducible unitary representation of P, and we consider the following two problems: (1) Extend this representation of P to a unitary representation of G. (2) Decompose tensor products of the resulting representations.

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Alexander Dvorsky, Siddhartha Sahi. 2001-10-31. Explicit Hilbert spaces for certain unipotent representations III. https://arxiv.org/abs/math/0110339

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