On universal graphs without instances of CH
نویسندگان
چکیده
منابع مشابه
On universal graphs without cliques or without large bipartite graphs
For every uncountable cardinal A, suitable negations of the Generalized Continuum Hypothesis imply: (a) There is no universal Ka 3. The instance Kuf^>t for A = Ni was settled in [KP] from a strengthening of CH.
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The theory of universal graphs originated from the observation of R. Rado [4,5] that a universal countable graph X exists, i.e., X is countable and isomorphically embeds every countable graph. He also showed that under GCH, there is a universal graph in every infinite cardinal. Since then, several results have been proved about the existence of universal elements in different classes of graphs....
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ژورنال
عنوان ژورنال: Annals of Pure and Applied Logic
سال: 1984
ISSN: 0168-0072
DOI: 10.1016/0168-0072(84)90042-3