Subnormal composition operators

Author:
Alan Lambert

Journal:
Proc. Amer. Math. Soc. **103** (1988), 750-754

MSC:
Primary 47B20; Secondary 47B38

DOI:
https://doi.org/10.1090/S0002-9939-1988-0947651-8

MathSciNet review:
947651

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Abstract: Let be the composition operator on given by , where is a -measurable transformation from onto and is strictly positive and bounded. It is shown that is a subnormal operator if and only if the sequence is a moment sequence for almost every point in . Several examples of subnormal composition operators are included.

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DOI:
https://doi.org/10.1090/S0002-9939-1988-0947651-8

Article copyright:
© Copyright 1988
American Mathematical Society