APM  Vol.2 No.5 , September 2012
On the Generality of Orthogonal Projections and e-Projections in Banach Algebras
ABSTRACT
In this paper we develop the orthogonal projections and e-projections in Banach algebras. We prove some necessary and sufficient conditions for them and their spectrums. We also show that the sum of two generalized orthogonal projections u and v is a generalized orthogonal projection if, uv=vu=0. Our results generalize the results obtained for bounded linear operators on Hilbert spaces.

Cite this paper
M. Asgari, S. Karimizad and H. Rahimi, "On the Generality of Orthogonal Projections and e-Projections in Banach Algebras," Advances in Pure Mathematics, Vol. 2 No. 5, 2012, pp. 318-322. doi: 10.4236/apm.2012.25044.
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