We show that p-hyponormal operators obey Weyl's and a-Weyl's theorem. Also, we show that the spectrum, Weyl spectrum, Browder spectrum and approximate point spectrum are continuous functions in the class of all p-hyponormal operators.
@article{bwmeta1.element.bwnjournal-article-smv143i1p23bwm,
author = {S. Djordjevi\'c and B. Duggal},
title = {Weyl's theorems and continuity of spectra in the class of p-hyponormal operators},
journal = {Studia Mathematica},
volume = {141},
year = {2000},
pages = {23-32},
zbl = {0984.47020},
language = {en},
url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-smv143i1p23bwm}
}
Djordjević, S.; Duggal, B. Weyl's theorems and continuity of spectra in the class of p-hyponormal operators. Studia Mathematica, Tome 141 (2000) pp. 23-32. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-smv143i1p23bwm/
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