Open Access
2013 Weyl type theorem and spectrum for $(p,k)$-quasiposinormal operators
D. Senthilkumar, D. Kiruthika , P. Maheswari Naik
Banach J. Math. Anal. 7(2): 30-41 (2013). DOI: 10.15352/bjma/1363784221
Abstract

Let $T$ be a $(p,k)$-quasiposinormal operator on a complex Hilbert space $\mathcal{H}$, i.e $T^{*k}(c^{2}(T^{*} T)^{p}-(T T^{*})^{p})T^{k} \geq 0$ for a positive integer $p \in (0,1]$, some $c > 0$ and a positive integer $k$. In this paper, we prove that the spectral mapping theorem for Weyl spectrum holds for $(p, k)$ - quasiposinormal operators. We show that the Weyl type theorems holds for $(p,k)$- quasiposinormal. We prove that if $T^{*}$ is $(p,k)$-quasiposinormal, then generalized $a$-Weyl's theorem holds for $T$. Also we prove that $\sigma_{jp}(T)-\{0\} = \sigma_{ap}(T)-\{0\}$ holds for $(p,k)$-quasiposinormal operator.

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Copyright © 2013 Tusi Mathematical Research Group
D. Senthilkumar, D. Kiruthika , and P. Maheswari Naik "Weyl type theorem and spectrum for $(p,k)$-quasiposinormal operators," Banach Journal of Mathematical Analysis 7(2), 30-41, (2013). https://doi.org/10.15352/bjma/1363784221
Published: 2013
Vol.7 • No. 2 • 2013
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