Journal of the Chungcheong Mathematical Society (충청수학회지)

The Chungcheong Mathematical Society (충청수학회)
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BACKWARD EXTENSION OF SUBNORMAL 2-VARIABLE WEIGHTED SHIFTS

  • Lee, Jun Ik (Department of Mathematics Education Sangmyung University)
  • Received : 2015.01.17
  • Accepted : 2015.04.24
  • Published : 2015.05.15
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Abstract

We study backward extensions of 2-variable weighted shifts with finite atomic Berger measure. We provide a necessary and sufficient condition for the subnormality of such extensions. As an application, we give a simple counterexample for the Curto-Muhly-Xia conjecture [10].

Keywords

References

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