arXiv 1111.71972011-11-30math.LO

Game representations of classes of piecewise definable functions

Luca Motto Ros

备注：: 19 pages
发表信息：: Mathematical Logic Quarterly 57 (2011), no.1, 95-112

英文摘要：

We present a general way of defining various reduction games on ω which "represent" corresponding topologically defined classes of functions. In particular, we will show how to construct games for piecewise defined functions, for functions which are pointwise limit of certain sequences of functions and for Γ-measurable functions. These games turn out to be useful as a combinatorial tool for the study of general reducibilities for subsets of the Baire space [10].

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