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Bergman Spaces on Disconnected Domains

Published online by Cambridge University Press:  20 November 2018

Alexandru Aleman
Affiliation:
Fachbereich Mathematik und Informatik, Fernuniversität Hagen, Postfach 940, 58084 Hagen, Germany, e-mail: Alexandru.Aleman@Fern Uni-Hagen.de
Stefan Richter
Affiliation:
Department of Mathematics, University of Tennessee, Knoxville, Tennessee, 37996-1300, U.S.A., e-mail: [email protected]
William T. Ross
Affiliation:
Department of Mathematics, University of Richmond, Richmond, Virginia 23173, U.S.A., e-mail: [email protected]
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Abstract

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For a bounded region G ⊂ ℂ and a compact set K ⊂ G, with area measure zero, we will characterize the invariant subspaces ℳ (under ƒ → zƒ) of the Bergman space (G \ K), 1 ≤ p < ∞, which contain (G) and with dim(ℳ/(z - λ)ℳ) = 1 for all λ ∈ G \ K. When G \ K is connected, we will see that dim(ℳ/(z - λ)ℳ) = 1 for all λ ∈ G \ K and thus in this case we will have a complete description of the invariant subspaces lying between (G) and (G \ K). When p = ∞, we will remark on the structure of the weak-star closed z-invariant subspaces between H(G) and H(G \ K). When G \ K is not connected, we will show that in general the invariant subspaces between (G) and (G \ K) are fantastically complicated. As an application of these results, we will remark on the complexity of the invariant subspaces (under ƒ → ζƒ) of certain Besov spaces on K. In particular, we shall see that in the harmonic Dirichlet space , there are invariant subspaces ℱ such that the dimension of ζℱ in ℱ is infinite.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1996

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