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Moment sequences and backward extensions of subnormal weighted shifts

Published online by Cambridge University Press:  09 April 2009

Thomas Hoover
Affiliation:
Department of Mathematics, University of Hawaii, Honolulu, Hawaii 96822, USA e-mail: [email protected]
Il Bong Jung
Affiliation:
Department of Mathematics, College of Natural Sciences, Kyungpook National UniversityTaegu 702-701Korea e-mail: [email protected]
Alan Lambert
Affiliation:
Department of Mathematics, University of North Carolina at Charlotte, UNCC Station Charlotte, NC 28223USA e-mail: [email protected]
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Abstract

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In this note we examine the relationships between a subnormal shift, the measure its moment sequence generates, and those of a large family of weighted shifts associated with the original shift. We examine the effects on subnormality of adding a new weight or changing a weight. We also obtain formulas for evaluating point mass at the origin for the measure associated with the shift. In addition, we examine the relationship between the measure associated with a subnormal shift and those of a family of shifts substantially different from the original shift.

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 2002

References

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