On Eigenvalues and Boundary Curvature of the Numerical Rang of Composition Operators on Hardy Space


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.

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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.

Conflicts of Interest

The authors declare no conflicts of interest.


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