Abstract
We study reducing subspaces for an analytic multiplication operator \({M_{z^{n}}}\) on the Bergman space \({L_{a}^{2}(A_{r})}\) of the annulus A r , and we prove that \({M_{z^{n}}}\) has exactly 2n reducing subspaces. Furthermore, in contrast to what happens for the disk, the same is true for the Hardy space on the annulus. Finally, we extend the results to certain bilateral weighted shifts, and interpret the results in the context of complex geometry.
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Research was partially supported by a grant from the National Science Foundation.
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Douglas, R.G., Kim, YS. Reducing Subspaces on the Annulus. Integr. Equ. Oper. Theory 70, 1–15 (2011). https://doi.org/10.1007/s00020-011-1874-3
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DOI: https://doi.org/10.1007/s00020-011-1874-3