On the Wadge reducibility of k-partitions
نویسنده
چکیده
We establish some results on the Wadge degrees and on the Boolean hierarchy of k-partitions of some spaces, where k is a natural number. The main attention is paid to the Baire space, Baire domain and their close relatives. For the case of Δ2-measurable k-partitions the structures of Wadge degrees are characterized completely. For many degree structures, undecidability of the first-order theories is shown, for any k ≥ 3.
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ورودعنوان ژورنال:
- J. Log. Algebr. Program.
دوره 79 شماره
صفحات -
تاریخ انتشار 2008