What Do Composition Operators Know about Inner Functions?
نویسنده
چکیده
This paper gives several different ways in which operator norms characterize those composition operators Cφ that arise from holomorphic self-maps φ of the unit disc that are inner functions. The setting is the Hardy space H of the disc, and the key result is a characterization of inner functions in terms of the asymptotic behavior of the Nevanlinna counting function.
منابع مشابه
Compact composition operators on certain analytic Lipschitz spaces
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