2014/07/27 by V. A. Vassiliev, Victor A. Vassiliev, Vassiliev, Victor A.
Mathematics · #Advanced Combinatorial Mathematics #Geometric and Algebraic Topology #Homotopy and Cohomology in Algebraic Topology #math.GT
paper · pdf · doi:10.48550/arxiv.1407.7235
arxiv created 2014/07/27 · arxiv updated 2014/07/29
We develop homological techniques for finding explicit combinatorial expressions of finite-type cohomology classes of spaces of knots in Rn, n ≥ 3, generalizing Polyak--Viro formulas for invariants (i.e. 0-dimensional cohomology classes) of knots in R3. As the first applications we give such formulas for the (reduced mod 2) \em generalized Teiblum--Turchin cocycle of order 3 (which is the simplest cohomology class of \em long knots R1 \hookrightarrow Rn not reducible to knot invariants or their natural stabilizations), and for all integral cohomology classes of orders 1 and 2 of spaces of \em compact knots S1 \hookrightarrow Rn. As a corollary, we prove the nontriviality of all these cohomology classes in spaces of knots in R3.