We investigate the shape of the numerical range for composition operators induced on the Hardy space H 2 by conformal automorphisms of the unit disc. We show that usually, but not always, such operators have numerical ranges whose closures are discs centered at the origin. Surprising open questions
Demiregular Convergence and the Theory of Numerical Ranges
β Scribed by R.U. Verma
- Publisher
- Elsevier Science
- Year
- 1995
- Tongue
- English
- Weight
- 229 KB
- Volume
- 193
- Category
- Article
- ISSN
- 0022-247X
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