Distances Between Composition Operators
نویسنده
چکیده
Composition operators Cφ induced by a selfmap φ of some set S are operators acting on a space consisting of functions on S by composition to the right with φ, that is Cφf = f ◦ φ. In this paper, we consider the Hilbert Hardy spaceH2 on the open unit disk and find exact formulas for distances ‖Cφ−Cψ‖ between composition operators. The selfmaps φ and ψ involved in those formulas are constant, inner, or analytic selfmaps of the unit disk fixing the origin. 2000Mathematics Subject Classification. Primary 47B33, Secondary 47B38
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