Examples from trees, related to discrete subsets, pseudo-radiality and omega-boundedness
Contribuinte(s) |
UNIVERSIDADE DE SÃO PAULO |
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Data(s) |
20/10/2012
20/10/2012
2009
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Resumo |
We construct some examples using trees. Some of them are consistent counterexamples for the discrete reflection of certain topological properties. All the properties dealt with here were already known to be non-discretely reflexive if we assume CH and we show that the same is true assuming the existence of a Suslin tree. In some cases we actually get some ZFC results. We construct also, using a Suslin tree, a compact space that is pseudo-radial but it is not discretely generated. With a similar construction, but using an Aronszajn tree, we present a ZFC space that is first countable, omega-bounded but is not strongly w-bounded, answering a question of Peter Nyikos. (C) 2008 Elsevier B.V. All rights reserved. |
Identificador |
TOPOLOGY AND ITS APPLICATIONS, v.156, n.4, p.775-782, 2009 0166-8641 http://producao.usp.br/handle/BDPI/30795 10.1016/j.topol.2008.09.015 |
Idioma(s) |
eng |
Publicador |
ELSEVIER SCIENCE BV |
Relação |
Topology and Its Applications |
Direitos |
restrictedAccess Copyright ELSEVIER SCIENCE BV |
Palavras-Chave | #Suslin trees #Aronszajn trees #Discrete reflection #omega-bounded #Discretely generated #Radial spaces #SPACES #SETS #Mathematics, Applied #Mathematics |
Tipo |
article original article publishedVersion |