Game Characterizations and Lower Cones in the Weihrauch Degrees
نویسندگان
چکیده
We introduce generalized Wadge games and show that each lower cone in the Weihrauch degrees is characterized by such a game. These generalized Wadge games subsume the original Wadge games, the eraser and backtrack games as well as variants of Semmes’ tree games. As a new example we introduce the tree derivative games which characterize all even finite levels of the Baire hierarchy, and a variant characterizing the odd finite levels.
منابع مشابه
Game characterizations of function classes and Weihrauch degrees
Games are an important tool in mathematics and logic, providing a clear and intuitive understanding of the notions they define or characterize. In particular, since the seminal work of Wadge in the 1970s, game characterizations of classes of functions in Baire space have been a rich area of research, having had significant and far-reaching development by van Wesep, Andretta, Duparc, Motto Ros, ...
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تاریخ انتشار 2017