Relationship Between the Goldberg Spectrum and the B-Fredholm Spectra
DOI:
https://doi.org/10.5644/SJM.13.1.06Keywords:
B-Fredholm operators, Quasi-Fredholm operators, Essential qausi-Fredholm spectrum, B-Fredholm spectrum, Transport operatorAbstract
A classical result of J. Ph. Labrousse (Rev. Roumaine Math. Pures Appl. 25, 1391-1394, 1980) concerning the symmetric difference between the essential quasi-Fredholm spectrum and the Goldberg spectrum of closed operators in Hilbert spaces is extended to the case of B-Fredholm spectra. The obtained results are used to describe the essential spectrum and some B-Fredholm spectra of some transport operators.
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References
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