Atomic compactness for reflexive graphs

• Autorzy: Christian Delhommé
• Języki publikacji: EN

Abstrakty

EN

A first order structure $\gotm$ with universe M is atomic compact if every system of atomic formulas with parameters in M is satisfiable in $\gotm$ provided each of its finite subsystems is. We consider atomic compactness for the class of reflexive (symmetric) graphs. In particular, we investigate the extent to which "sparse" graphs (i.e. graphs with "few" vertices of "high" degree) are compact with respect to systems of atomic formulas with "few" unknowns, on the one hand, and are pure restrictions of their Stone-Čech compactifications, on the other hand.

Kategorie tematyczne

• 03C50: Models with special properties (saturated, rigid, etc.)
• 05C99: None of the above, but in this section

• Wydawca: Institute of Mathematics Polish Academy of Sciences
• Czasopismo: Fundamenta Mathematicae
• Rocznik: 1999
• Tom: 162
• Numer: 2
• Strony: 99-117

Daty

wydano

1999

otrzymano

1997-04-14

poprawiono

1999-02-27

Twórcy

autor

Christian Delhommé

• Université de la Réunion 15, avenue René Cassin, BP 7151, 97715 Saint Denis Messag. Cedex 9, France

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