Polish group actions and effectivity
نویسندگان
چکیده
منابع مشابه
Computable Polish Group Actions
Using methods from computable analysis, we establish a new connection between two seemingly distant areas of logic: computable structure theory and invariant descriptive set theory. We extend several fundamental results of computable structure theory to the more general setting of topological group actions. Among other results, we provide a new recursion-theoretic characterization of Σ3-orbits ...
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The results in this paper involve two different topics in the descriptive theory of Polish group actions. The book Becker-Kechris [6] is an introduction to that theory. Our two topics—and two collections of theorems—are rather unrelated, but the proofs for both topics are essentially the same. Locally compact Polish groups, i.e., second countable locally compact groups, are the traditional obje...
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ژورنال
عنوان ژورنال: Archive for Mathematical Logic
سال: 2012
ISSN: 0933-5846,1432-0665
DOI: 10.1007/s00153-012-0282-y