On the number of automorphism of uncontable models

Saharon Shelah; Heikki Tuuri; Jouko Väänänen

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On the number of automorphism of uncontable models

Saharon Shelah·Heikki Tuuri·Jouko Väänänen

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Abstract

Let s(A) denote the number of automorphisms of a model A of power omega_1. We derive a necessary and sufficient condition in terms of trees for the existence of an A with omega_1 < s(A) < 2^{omega_1}. We study the sufficiency of some conditions for s(A)=2^{omega_1}. These conditions are analogous to conditions studied by D.Kueker in connection with countable models.

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BibTeX RIS

Saharon Shelah, Heikki Tuuri, Jouko Väänänen. 1993-01-15. On the number of automorphism of uncontable models. https://arxiv.org/abs/math/9301205

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