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SUBNORMAL WEIGHTED SHIFTS WHOSE MOMENT MEASURES HAVE POSITIVE MASS AT THE ORIGIN

  • Lee, Mi Ryeong (DEPARTMENT OF MATHEMATICS, KYUNGPOOK NATIONAL UNIVERSITY) ;
  • Kim, Kyung Mi (DEPARTMENT OF MATHEMATICS, KYUNGPOOK NATIONAL UNIVERSITY)
  • Received : 2012.01.26
  • Accepted : 2012.11.19
  • Published : 2012.12.25

Abstract

In this note we examine the effects on subnormality of adding a new weight or changing some weights for a given subnormal weighted shift. We consider a subnormal weighted shift with a positive point mass at the origin by means of continuous functions. Finally, we introduce some methods for evaluating point mass at the origin about moment measures associated with weighted shifts.

Acknowledgement

Supported by : National Research Foundation of Korea(NRF)

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