How Incomputable Is the Separable Hahn-Banach Theorem?
نویسندگان
چکیده
منابع مشابه
How Incomputable is the Separable Hahn-Banach Theorem?
We determine the computational complexity of the Hahn-Banach Extension Theorem. To do so, we investigate some basic connections between reverse mathematics and computable analysis. In particular, we use Weak König’s Lemma within the framework of computable analysis to classify incomputable functions of low complexity. By defining the multi-valued function Sep and a natural notion of reducibilit...
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ژورنال
عنوان ژورنال: Notre Dame Journal of Formal Logic
سال: 2009
ISSN: 0029-4527
DOI: 10.1215/00294527-2009-018