On classes of T0 spaces admitting completions

• Giuli, Eraldo ^[1]
  1. [1] Università di L'Aquila
• Localización: Applied general topology, ISSN-e 1989-4147, ISSN 1576-9402, Vol. 4, Nº. 1, 2003, págs. 143-155
• Idioma: inglés
• DOI: 10.4995/agt.2003.2016
• Enlaces
  • Texto completo
• Resumen

  • For a given class X of T0 spaces the existence of a subclass C, having the same properties that the class of complete metric spaces has in the class of all metric spaces and non-expansive maps, is investigated. A positive example is the class of all T0 spaces, with C the class of sober T0 spaces, and a negative example is the class of Tychonoff spaces. We prove that X has the previous property (i.e., admits completions) whenever it is the class of T0 spaces of an hereditary coreflective subcategory of a suitable supercategory of the category Top of topological spaces. Two classes of examples are provided.

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