Automorphism groups and Ramsey properties of sparse graphs
نویسندگان
چکیده
We study automorphism groups of sparse graphs from the viewpoint of topological dynamics and the Kechris, Pestov, Todorčević correspondence. We investigate amenable and extremely amenable subgroups of these groups using the space of orientations of the graph and results from structural Ramsey theory. Resolving one of the open questions in the area, we show that Hrushovski’s example of an ω-categorical sparse graph has no ω-categorical expansion with extremely amenable automorphism
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ورودعنوان ژورنال:
- CoRR
دوره abs/1801.01165 شماره
صفحات -
تاریخ انتشار 2018