Pseudocharacters of groups have recently found an application in the theory of classical knots and links in R3. More precisely, there is a relationship between pseudocharacters of Artin's braid groups and the properties of links represented by braids. In the paper, this relationship is investigated and the notion of kernel pseudocharacters of braid groups is introduced. It is proved that if a kernel pseudocharacter φ and a braid β satisfy |φ(β)| > Cφ, where Cφ is the defect of φ, then β represents a prime link (i.e., a link that is noncomposite, nonsplit, and nontrivial). Furthermore, the space of braid group pseudocharacters is studied and a way is described to obtain nontrivial kernel pseudocharacters from an arbitrary braid group pseudocharacter that is not a homomorphism. This makes it possible to employ an arbitrary nontrivial braid group pseudocharacter for the recognition of prime knots and links.

Original languageRussian
Pages (from-to)245-259
Number of pages15
JournalSt. Petersburg Mathematical Journal
Volume21
Issue number2
DOIs
StatePublished - 1 Dec 2010

    Scopus subject areas

  • Analysis
  • Algebra and Number Theory
  • Applied Mathematics

    Research areas

  • Braid, Knot, Link, Pseudocharacter, Quasimorphism

ID: 47487598