Virtual link and knot invariants from non-abelian Yang-Baxter 2-cocycle pairs (1707.02250v2)

Abstract: For a given $(X,S,\beta)$, where $S,\beta\colon X\times X\to X\times X$ are set theoretical solutions of Yang-Baxter equation with a compatibility condition, we define an invariant for virtual (or classical) knots/links using non commutative 2-cocycles pairs $(f,g)$ that generalizes the one defined in [FG2]. We also define, a group $U_{nc}^{fg}=U_{nc}^{fg}(X,S,\beta)$ and functions $\pi_f, \pi_g\colon X\times X\to U_{nc}^{fg}(X)$ governing all 2-cocycles in $X$. We exhibit examples of computations achieved using GAP.