Polish group actions and computability

Aleksander Ivanov; Barbara Majcher-Iwanow

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arXiv · 0903.1070

Polish group actions and computability

Aleksander Ivanov·Barbara Majcher-Iwanow

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Abstract

Let G be a closed subgroup of the group of all permutations of a countably infinite set. Let X be a Polish G-space with a countable basis A of clopen sets. Each x from X defines a characteristic function f on A by f(U)=1 iff x belongs to U (where U is from A). We consider computable complexity of f and some related questions.

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BibTeX RIS

Aleksander Ivanov, Barbara Majcher-Iwanow. 2009-08-09. Polish group actions and computability. https://arxiv.org/abs/0903.1070

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