Multicentric representation and von Neumann spectral sets
نویسنده
چکیده
Aalto University, P.O. Box 11000, FI-00076 Aalto www.aalto.fi Author Olavi Nevanlinna Name of the publication Multicentric representation and von Neumann spectral sets Publisher School of Science Unit Department of Mathematics and Systems Analysis Series Aalto University publication series SCIENCE + TECHNOLOGY 11/2011 Field of research Mathematics Abstract We show how multicentric representation of functions provides a simple way to generalize the von Neumann result that the unit disc is a spectral set for contractions in Hilbert spaces. In particular the sets need not be connected and the results can be applied to bounding Riesz spectral projections.We show how multicentric representation of functions provides a simple way to generalize the von Neumann result that the unit disc is a spectral set for contractions in Hilbert spaces. In particular the sets need not be connected and the results can be applied to bounding Riesz spectral projections.
منابع مشابه
Spectral Sets
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