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arXiv · 1602.05398

The reverse mathematics of the Tietze extension theorem

Paul Shafer
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Abstract

We prove that several versions of the Tietze extension theorem for functions with moduli of uniform continuity are equivalent to WKL_0 over RCA_0. This confirms a conjecture of Giusto and Simpson that was also phrased as a question in Montalb\'an's "Open questions in reverse mathematics."

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Paul Shafer. 2016-02-17. The reverse mathematics of the Tietze extension theorem. https://arxiv.org/abs/1602.05398

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