翻訳と辞書 Words near each other ・ Martin McKay ・ Martin McKeay ・ Martin McKee ・ Martin McKinnon ・ Martin McLaren ・ Martin McLaughlin ・ Martin McLoughlin ・ Martin McManus (Australian politician) ・ Martin McNamara ・ Martin McNamara (hurler) ・ Martin McNeil ・ Martin McNiff ・ Martin McNulty Crane ・ Martin McQuade ・ Martin McQuillan ・ Martin measure ・ Martin Medlar ・ Martin Meehan ・ Martin Meehan (Irish republican) ・ Martin Mehkek ・ Martin Meichelbeck ・ Martin Meissonnier ・ Martin Mejstřík ・ Martin Melcher ・ Martin Melin ・ Martin Melvin ・ Martin Mere ・ Martin Meredith ・ Martin Merton ・ Martin Mesík Dictionary Lists mini英和辞書 mini和英辞書 Webster 1913 Latin-English FOLDOC Wikipedia English ウィキペディア

翻訳と辞書　辞書検索 [ 開発暫定版 ] スポンサード リンク Martin measure ： ウィキペディア英語版 Martin measure In descriptive set theory, the Martin measure is a filter on the set of Turing degrees of sets of natural numbers, named after Donald A. Martin. Under the axiom of determinacy it can be shown to be an ultrafilter. == Definition == Let $D$ be the set of Turing degrees of sets of natural numbers. Given some equivalence class $()\backslash in\; D$, we may define the ''cone'' (or ''upward cone'') of $()$ as the set of all Turing degrees $()$ such that $X\backslash le\_T\; Y$; that is, the set of Turing degrees which are "more complex" than $X$ under Turing reduction. We say that a set $A$ of Turing degrees has measure 1 under the Martin measure exactly when $A$ contains some cone. Since it is possible, for any $A$, to construct a game in which player I has a winning strategy exactly when $A$ contains a cone and in which player II has a winning strategy exactly when the complement of $A$ contains a cone, the axiom of determinacy implies that the measure-1 sets of Turing degrees form an ultrafilter. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Martin measure」の詳細全文を読む スポンサード リンク 翻訳と辞書 : 翻訳のためのインターネットリソース Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.