A decomposition of Brouwer's fan theorem
نویسنده
چکیده
We introduce axioms LFAN and CFAN , where the former follows from the law of excluded middle and the latter follows from the axiom of countable choice. Then we show that Brouwer’s fan theorem is constructively equivalent to LFAN + CFAN . This decomposition of the fan theorem into a logical axiom and a function existence axiom contributes to the programme of constructive reverse mathematics. 2000 Mathematics Subject Classification 03F03, 03F55 (primary); 03F60 (secondary)
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ورودعنوان ژورنال:
- J. Logic & Analysis
دوره 1 شماره
صفحات -
تاریخ انتشار 2009