## Linear fractional composition operators on $$H^ 2$$.(English)Zbl 0638.47027

Let $$\phi$$ be an analytic function mapping the unit disk D into itself. The composition operator $$C_{\phi}$$ on $$H_ 2$$ is defined by $$C_{\phi}f=f\circ \phi$$. In this paper the author studies such composition operators when $$\phi$$ is a linear fractional transformation. For example, the author considers the computation of the adjoint and the operator norm for certain such composition operators.
Reviewer: Ch.Swartz

### MSC:

 47B38 Linear operators on function spaces (general) 46J15 Banach algebras of differentiable or analytic functions, $$H^p$$-spaces
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### References:

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