Algebraic structures of Vassiliev invariants for knot families

Abstract: We explore algebraic relations on Vassiliev knot invariants expressed through correlators in the 3-dimensional Chern-Simons theory. Vassiliev invariants form an infinite-dimensional algebra. We focus on $k$-parametric knot families with Vassiliev invariants being polynomials in family parameters. It turns out that such a 1-parametric algebra of Vassiliev invariants is always finitely generated, while in the case of more parameters, the number of generators can be infinite. Inside a knot family, there appear extra algebraic relations on Vassiliev invariants. We show that there are $\leq k$ algebraically independent Vassiliev invariants for a $k$-parametric knot family. However, in all our examples, the number of algebraically independent Vassiliev invariants is exactly $k$, and it is an open question if there exists a $k$-parametric knot family with a fewer number of algebraically independent Vassiliev invariants. We also demonstrate that a complete knot invariant of some $k$-parametric knot families consists of $\leq k$ Vassiliev invariants. Again, we have only examples of a set of $k$ Vassiliev invariants being a complete invariant of a $k$-parametric knot family. Currently, it is unknown whether a set of a fewer number of Vassiliev invariants cannot be a complete knot family invariant.