Abstract
For a domain Ω in ℂd and a Hilbert space ℋ of analytic functions on Ω which satisfies certain conditions, we characterize the commuting d-tuples T = (T1,...,Td) of operators on a separable Hilbert space H such that T* is unitarily equivalent to the restriction of M* to an invariant subspace, where M is the operator d-tuple Z ⊗ I on the Hilbert space tensor product ℋ ⊗ H. For Ω the unit disc and ℋ the Hardy space H2, this reduces to a well-known theorem of Sz.-Nagy and Foias; for ℋ a reproducing kernel Hilbert space on Ω ⊂ ℂd such that the reciprocal 1/K (x,ȳ) of its reproducing kernel is a polynomial in x and ȳ, this is a recent result of Ambrozie, Müller and the second author. In this paper, we extend the latter result by treating spaces ℋ for which 1/K ceases to be a polynomial, or even has a pole: namely, the standard weighted Bergman spaces (or, rather, their analytic continuation) ℋ = ℋv on a Cartan domain corresponding to the parameter v in the continuous Wallach set, and reproducing kernel Hilbert spaces ℋ for which 1/ K is a rational function. Further, we treat also the more general problem when the operator M is replaced by M ⊕ W, W being a certain generalization of a unitary operator tuple. For the case of the spaces ℋv on Cartan domains, our results are based on an analysis of the homogeneous multiplication operators on Ω, which seems to be of an independent interest.
Original language | English |
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Pages (from-to) | 837-864 |
Number of pages | 28 |
Journal | Transactions of the American Mathematical Society |
Volume | 355 |
Issue number | 2 |
State | Published - Feb 2003 |
Keywords
- Bounded symmetric domains
- Coanalytic models
- Commuting operator tuples
- Functional calculus
- Reproducing kernels
ASJC Scopus subject areas
- General Mathematics
- Applied Mathematics