Reducts of structures and maximal-closed permutation groups

Manuel Bodirsky; Dugald Macpherson

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arXiv · 1310.6393

Reducts of structures and maximal-closed permutation groups

Manuel Bodirsky·Dugald Macpherson

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Abstract

Answering a question of Junker and Ziegler, we construct a countable first order structure which is not omega-categorical, but does not have any proper non-trivial reducts, in either of two senses (model-theoretic, and group-theoretic). We also construct a strongly minimal set which is not omega-categorical but has no proper non-trivial reducts in the model-theoretic sense.

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BibTeX RIS

Manuel Bodirsky, Dugald Macpherson. 2015-02-26. Reducts of structures and maximal-closed permutation groups. https://arxiv.org/abs/1310.6393

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