Braids in trivial braid diagrams

نویسندگان

  • Patrick Dehornoy
  • PATRICK DEHORNOY
چکیده

We show that every trivial 3-strand braid diagram contains a disk, defined as a ribbon ending in opposed crossings. Under a convenient algebraic form, the result extends to every Artin–Tits group of dihedral type, but it fails to extend to braids with 4 strands and more. The proof uses a partition of the Cayley graph and a continuity argument.

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تاریخ انتشار 2017