Composition operators between Toeplitz kernels

• Liang, Yuxia ^[1] ; Partington, Jonathan R. ^[2]
  1. [1] Tianjin Normal University

     Tianjin Normal University

     China

     
  2. [2] University of Leeds

     University of Leeds

     Reino Unido

     
• Localización: Collectanea mathematica, ISSN 0010-0757, Vol. 77, Fasc. 3, 2026, págs. 861-881
• Idioma: inglés
• DOI: 10.1007/s13348-025-00495-7
• Texto completo no disponible (Saber más ...)
• Resumen

  • Recently, it was shown that the image of a Toeplitz kernel of dimension greater than 1 under composition by an inner function is nearly S^*-invariant if and only if the inner function is an automorphism. Building on this, we determine the minimal Toeplitz kernel containing the image of a Toeplitz kernel under a composition operator with a general inner symbol, and extend this to weighted composition operators. Specifically, the corresponding cases for minimal model spaces are also given, thereby extending known work on the action of composition operators on model spaces. Finally, we use the equivalences between Toeplitz kernels to derive the explicit maximal vectors for several Toeplitz kernels, with symbols expressed in terms of composition operators and inner functions.

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