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Sphere recognition lies in NP

Saul Schleimer
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Abstract

We prove that the three-sphere recognition problem lies in the complexity class NP. Our work relies on Thompson's original proof that the problem is decidable [Math. Res. Let., 1994], Casson's version of her algorithm, and recent results of Agol, Hass, and Thurston [ArXiv, 2002].

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Saul Schleimer. 2004-07-05. Sphere recognition lies in NP. https://arxiv.org/abs/math/0407047

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