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 APM  Vol.5 No.6 , May 2015
On Eigenvalues and Boundary Curvature of the Numerical Rang of Composition Operators on Hardy Space
Abstract: For a bounded linear operator A on a Hilbert space H, let M(A) be the smallest possible constant in the inequality . Here, p is a point on the smooth portion of the boundary of the numerical range of A. is the radius of curvature of at this point and  is the distance from p to the spectrum of A. In this paper, we compute the M(A) for composition operators on Hardy space H2.
Cite this paper: Heydari, M. (2015) On Eigenvalues and Boundary Curvature of the Numerical Rang of Composition Operators on Hardy Space. Advances in Pure Mathematics, 5, 333-337. doi: 10.4236/apm.2015.56032.
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