Ω-powers and Descriptive Set Theory
نویسنده
چکیده
We study the sets of the infinite sentences constructible with a dictionary over a finite alphabet, from the viewpoint of descriptive set theory. Among other things, this gives some true co-analytic sets. The case where the dictionary is finite is studied and gives a natural example of a set at the level ω of the Wadge hierarchy.
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ورودعنوان ژورنال:
- J. Symb. Log.
دوره 70 شماره
صفحات -
تاریخ انتشار 2005