Potential Wadge classes
نویسنده
چکیده
Let Γ be a Borel class, or a Wadge class of Borel sets, and 2≤d≤ω a cardinal. We study the Borel subsets of R that can be made Γ by refining the Polish topology on the real line. These sets are called potentially Γ. We give a test to recognize potentially Γ sets. 2010 Mathematics Subject Classification. Primary: 03E15, Secondary: 54H05, 28A05, 26A21
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