Notes on q-deformed operators

Schôichi Ôta, Franciszek Hugon Szafraniec
2004 Studia Mathematica  
The paper concerns operators of deformed structure like q-normal and qhyponormal operators with the deformation parameter q being a positive number different from 1. In particular, an example of a q-hyponormal operator with empty spectrum is given, and q-hyponormality is characterized in terms of some operator inequalities. 2000 Mathematics Subject Classification: 47A05, 47A10, 47B25.
doi:10.4064/sm165-3-7 fatcat:diwib6yicrbjdp3cdjgnaeakcu