Polish Group Actions and Computability
نویسندگان
چکیده
Let G be a closed subgroup of S∞ and X be a Polish G-space with a countable basisA of clopen sets. Each x ∈ X defines a characteristic function τx on A by τx(A) = 1 ⇔ x ∈ A. We consider computable complexity of τx and some related questions.
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تاریخ انتشار 2009