Coarse groups, and the isomorphism problem for oligomorphic groups
Coarse groups, and the isomorphism problem for oligomorphic groups
Let [Formula: see text] denote the topological group of permutations of the natural numbers. A closed subgroup G of [Formula: see text] is called oligomorphic if for each n, its natural action on n-tuples of natural numbers has only finitely many orbits. We study the complexity of the topological isomorphism …