Distances between composition operators

• Autores: Valentin Matache
• Localización: Extracta mathematicae, ISSN-e 0213-8743, Vol. 22, Nº 1, 2007, págs. 19-34
• Idioma: inglés
• Títulos paralelos:
  • Distancias entre operadores de composición
• Enlaces
  • Texto completo  1    2 (pdf) 
• Resumen

  • Composition operators Cf induced by a selfmap f of some set S are operators acting on a space consisting of functions on S by composition to the right with f, that is Cff = f º f. In this paper, we consider the Hilbert Hardy space H2 on the open unit disk and find exact formulas for distances ||Cf - C?|| between composition operators. The selfmaps f and ? involved in those formulas are constant, inner, or analytic selfmaps of the unit disk fixing the origin.