Spread of balleans

• Filali, Mahmoud ^[1] ; Protasov, Igor V. ^[2]
  1. [1] University of Oulu

     University of Oulu

     Oulu, Finlandia

     
  2. [2] Kyiv University
• Localización: Applied general topology, ISSN-e 1989-4147, ISSN 1576-9402, Vol. 9, Nº. 2, 2008, págs. 169-175
• Idioma: inglés
• DOI: 10.4995/agt.2008.1796
• Enlaces
  • Texto completo
• Resumen

  • A ballean is a set endowed with some family of balls in such a way that a ballean can be considered as an asymptotic counterpart of a uniform topological space. We introduce and study a new cardinal invariant called the spread of a ballean. In particular, we show that, for every ordinal ballean B, spread of B coincides with density of B.

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