Definability in Infinitary Languages and Invariance by Automorphisms
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RIS BIB ENDNOTEDefinability in Infinitary Languages and Invariance by Automorphisms
Publication date: 20.09.2010
Reports on Mathematical Logic, 2010, Number 45, pp. 119-133
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Definability in Infinitary Languages and Invariance by Automorphisms
Given a L-alpha beta(E)-structure E, where L-alpha beta(E) is an infinitary language, we show that alpha and beta can be chosen in such way that every orbit of the group G of automorphisms of E is L-alpha beta(E)-definable. It follows that two sequences of elements of the domain D of E satisfy the same set of L-alpha beta-formulas if and only if they are in the same orbit of G
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Information: Reports on Mathematical Logic, 2010, Number 45, pp. 119-133
Article type: Original article
University of Sao Paulo
Brazil
Universidade Federal da Bahia, Bahia, Brasil
Pontifical Catholic University of São Paulo, São Paulo, Brazil
Published at: 20.09.2010
Article status: Open
Licence: None
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