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arXiv · 1908.05249

Simplicity of the automorphism groups of order and tournament expansions of homogeneous structures

Filippo Calderoni·Aleksandra Kwiatkowska·Katrin Tent
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Abstract

We define the notions of a free fusion of structures and a weakly stationary independence relation. We apply these notions to prove simplicity for the automorphism groups of order and tournament expansions of homogeneous structures like the bounded Urysohn space, the random graph, and the random poset.

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Filippo Calderoni, Aleksandra Kwiatkowska, Katrin Tent. 2019-08-14. Simplicity of the automorphism groups of order and tournament expansions of homogeneous structures. https://doi.org/10.1016/j.jalgebra.2021.03.028

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