Iteration of functions and contractibility of acyclic 2-complexes

• Autores: Ian J. Leary
• Localización: Publicacions matematiques, ISSN 0214-1493, Vol. 65, Nº 1, 2021, págs. 309-318
• Idioma: inglés
• DOI: 10.5565/publicacionsmatematiques.v65i1.383987
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• Resumen

  • We show that there can be no algorithm to decide whether infinite recursively described acyclic aspherical 2-complexes are contractible. We construct such a complex that is contractible if and only if the Collatz conjecture holds.

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