Ball proximinality of closed * subalgebras in C(Q)

• Autores: Indumathi Vedarethinam, S. Lalithambigai, Bor-Luh Lin
• Localización: Extracta mathematicae, ISSN-e 0213-8743, Vol. 22, Nº 1, 2007, págs. 1-18
• Idioma: inglés
• Títulos paralelos:
  • Proximinalidad de bola de subálgebras * cerradas en C(Q)
• Enlaces
  • Texto completo  1    2 (pdf) 
• Resumen

  • The notion of ball proximinality and the strong ball proximinality were recently introduced in [2]. We prove that a closed * subalgebra A of C(Q) is strongly ball proximinal in C(Q) and the metric projection from C(Q), onto the closed unit ball of A, is Hausdorff metric continuous and hence has continuous selection.