Extension properties and the Niemytzki plane

• Ohta, Haruto ^[1]
  1. [1] Shizuoka University

     Shizuoka University

     Aoi-ku, Japón

     
• Localización: Applied general topology, ISSN-e 1989-4147, ISSN 1576-9402, Vol. 1, Nº. 1, 2000, págs. 45-60
• Idioma: inglés
• DOI: 10.4995/agt.2000.3023
• Enlaces
  • Texto completo
• Resumen

  • The first part of the paper is a brief survey on recent topics concerning the relationship between C*-embedding and C-embedding for closed subsets. The second part studies extension properties of the Niemytzki plane NO. A zero-set, z-; C*-, and P-embedded subsets of NP are determined. Finally, we prove that every C*-embedded subset of NP is a P-embedded zero-set, which answers a problem raised in the first part.

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