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A characterization of subnormal operators

Published online by Cambridge University Press:  18 May 2009

Alan Lambert
Affiliation:
The Weizmann Institute of Science, Rehovot, Israel
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In this note a characterization of subnormality of operators on Hilbert space is given. The characterization is in terms of a sequence of polynomials in the operator and its adjoint reminiscent of the binomial expansion in commutative algebras. As such no external Hilbert spaces are needed, nor is it necessary to introduce forms dependent on arbitrary sequences of vectors from the Hilbert space.

Type
Research Article
Copyright
Copyright © Glasgow Mathematical Journal Trust 1984

References

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