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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