Abstract
We prove that every one-dimensional extension of a bitriangular operator has a cyclic commutant. We also prove that ifT is an extension of a bitriangular operator by an algebraic operator, then the weakly closed algebraW(T) generated byT has a separating vector.
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This work was partially supported by NSF Grant DMS-9401544.
Participant, Workshop in Linear Analysis and Probability, Texas A&M University
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Larson, D.R., Wogen, W.R. Extensions of bitriangular operators. Integr equ oper theory 25, 216–223 (1996). https://doi.org/10.1007/BF01308631
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DOI: https://doi.org/10.1007/BF01308631