Sphere Recognition Lies in Np
نویسنده
چکیده
We prove that the three-sphere recognition problem lies in NP. Rubinstein [Haifa, 1992] and Thompson [Math. Res. Let., 1994] showed that the problem is decidable. Our result relies on Casson’s version [MSRI, 1997] of their algorithm and recent results of Agol, Hass, and Thurston [STOC, 2002].
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