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Minimal triangulations of circle bundles, circular permutations and binary Chern cocycle

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 نشر من قبل Nikolai Mnev
 تاريخ النشر 2019
  مجال البحث
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 تأليف Nikolai Mnev




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We investigate a PL topology question: which circle bundles can be triangulated over a given triangulation of the base? The question got a simple answer emphasizing the role of minimal triangulations encoded by local systems of circular permutations of vertices of the base simplices. The answer is based on an experimental fact: classical Huntington transitivity axiom for cyclic orders can be expressed as the universal binary Chern cocycle.



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