Notre Dame Journal of Formal Logic

Lascar Types and Lascar Automorphisms in Abstract Elementary Classes

Tapani Hyttinen and Meeri Kesälä

Abstract

We study Lascar strong types and Galois types and especially their relation to notions of type which have finite character. We define a notion of a strong type with finite character, the so-called Lascar type. We show that this notion is stronger than Galois type over countable sets in simple and superstable finitary AECs. Furthermore, we give an example where the Galois type itself does not have finite character in such a class.

Article information

Source
Notre Dame J. Formal Logic, Volume 52, Number 1 (2011), 39-54.

Dates
First available in Project Euclid: 13 December 2010

Permanent link to this document
https://projecteuclid.org/euclid.ndjfl/1292249609

Digital Object Identifier
doi:10.1215/00294527-2010-035

Mathematical Reviews number (MathSciNet)
MR2747161

Zentralblatt MATH identifier
1233.03038

Subjects
Primary: 03C45: Classification theory, stability and related concepts [See also 03C48]
Secondary: 03C52: Properties of classes of models

Keywords
geometric stability theory abstract elementary classes

Citation

Hyttinen, Tapani; Kesälä, Meeri. Lascar Types and Lascar Automorphisms in Abstract Elementary Classes. Notre Dame J. Formal Logic 52 (2011), no. 1, 39--54. doi:10.1215/00294527-2010-035. https://projecteuclid.org/euclid.ndjfl/1292249609


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