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http://dx.doi.org/10.14403/jcms.2015.28.2.261

BACKWARD EXTENSION OF SUBNORMAL 2-VARIABLE WEIGHTED SHIFTS  

Lee, Jun Ik (Department of Mathematics Education Sangmyung University)
Publication Information
Journal of the Chungcheong Mathematical Society / v.28, no.2, 2015 , pp. 261-267 More about this Journal
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
one-step extension; 2-variable weighted shifts; subnormal pair; Berger measure;
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