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Keywords:
sparse graph; Hrushovski construction; admissible order; meagre orbit; orientation
sparse graph; Hrushovski construction; admissible order; meagre orbit; orientation
Summary:
We consider the topological dynamics of the automorphism group of a particular sparse graph $M_1$ resulting from an ab initio Hrushovski construction. We show that minimal subflows of the flow of linear orders on $M_1$ have all orbits meagre, partially answering a question of T. Tsankov regarding results of D. M. Evans, J. Hubička and J. Nešetřil on the topological dynamics of automorphism groups of sparse graphs.
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