Orbitally discrete coarse spaces

• Protasov, Igor V. ^[1]
  1. [1] Taras Shevchenko National University of Kyiv

     Taras Shevchenko National University of Kyiv

     Ucrania

     
• Localización: Applied general topology, ISSN-e 1989-4147, ISSN 1576-9402, Vol. 22, Nº. 2, 2021, págs. 303-309
• Idioma: inglés
• DOI: 10.4995/agt.2021.13874
• Enlaces
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• Resumen

  • Given a coarse space (X, E), we endow X with the discrete topology and denote X ♯ = {p ∈ βG : each member P ∈ p is unbounded }. For p, q ∈ X ♯ , p||q means that there exists an entourage E ∈ E such that E[P] ∈ q for each P ∈ p. We say that (X, E) is orbitally discrete if, for every p ∈ X ♯ , the orbit p = {q ∈ X ♯ : p||q} is discrete in βG. We prove that every orbitally discrete space is almost finitary and scattered.

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