Abstract
We present sufficient conditions in order (the space of) a Riesz operator T in a Hilbert space H have a Jordan-Schur basis with respect to a scalar product equivalent to the original one. This is related to Schur’s lemma for a compact operator, which is an extension of Schur’s classical theorem on unitary triangularization in a finite dimensional space. The finite dimensional case is also studied.
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Communicated by L. Kérchy
This research was supported by the Hungarian OTKA Grant No. K77748.
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Nagy, B. Riesz operators and Schur’s lemma. ActaSci.Math. 80, 639–650 (2014). https://doi.org/10.14232/actasm-012-092-8
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DOI: https://doi.org/10.14232/actasm-012-092-8
Key words and phrases
- Riesz operator
- Schur’s lemma
- unitary triangularization
- equivalent scalar product
- Jordan-Schur basis
- spectral operator
- resolution of the identity