Drinfeld–Manin solutions of the Yang–Baxter equation coming from cube complexes

The most common geometric interpretation of the Yang–Baxter equation is by braids, knots and relevant Reidemeister moves. So far, cubes were used for connections with the third Reidemeister move only. We will show that there are higher-dimensional cube complexes solving the [Formula: see text]-state Yang–Baxter equation for arbitrarily large [Formula: see text]. More precisely, we introduce explicit constructions of cube complexes covered by products of [Formula: see text] trees and show that these cube complexes lead to new solutions of the Yang–Baxter equations.

Space of chord diagrams on spherical curves

In this paper, we give a definition of [Formula: see text]-valued functions from the ambient isotopy classes of spherical/plane curves derived from chord diagrams, denoted by [Formula: see text]. Then, we introduce certain elements of the free [Formula: see text]-module generated by the chord diagrams with at most [Formula: see text] chords, called relators of Type (I) ((SI[Formula: see text]I), (WI[Formula: see text]I), (SI[Formula: see text]I[Formula: see text]I), or (WI[Formula: see text]I[Formula: see text]I), respectively), and introduce another function [Formula: see text] derived from [Formula: see text]. The main result (Theorem 1) shows that if [Formula: see text] vanishes for the relators of Type (I) ((SI[Formula: see text]I), (WI[Formula: see text]I), (SI[Formula: see text]I[Formula: see text]I), or (WI[Formula: see text]I[Formula: see text]I), respectively), then [Formula: see text] is invariant under the Reidemeister move of type RI (strong RI[Formula: see text]I, weak RI[Formula: see text]I, strong RI[Formula: see text]I[Formula: see text]I, or weak RI[Formula: see text]I[Formula: see text]I, respectively) that is defined in [N. Ito and Y. Takimura, [Formula: see text] and weak [Formula: see text] homotopies on knot projections, J. Knot Theory Ramifications 22 (2013) 1350085 14 pp].

Virtual crossings and a filtration of the triply graded link homology of a link diagram

A filtration of Soergel bimodules by virtual crossing bimodules extends to Rouquier’s complexes associated with braid words. We show that these complexes are invariant up to filtered homotopy with respect to the second Reidemeister move, and the filtration of the triply graded link diagram homology, constructed by Khovanov through the application of the Hochschild homology, is invariant under Markov moves. We also prove that the homotopy equivalence of the complexes of braid words related by the third Reidemeister move violates filtration by at most two units.

(1, 2) AND WEAK (1, 3) HOMOTOPIES ON KNOT PROJECTIONS

In this paper, we obtain the necessary and sufficient condition that two knot projections are related by a finite sequence of the first and second flat Reidemeister moves (Theorem 2.2). We also consider an equivalence relation that is called weak (1, 3) homotopy. This equivalence relation occurs by the first flat Reidemeister move and one of the third flat Reidemeister moves. We introduce a map sending weak (1, 3) homotopy classes to knot isotopy classes (Sec. 3). Using the map, we determine which knot projections are trivialized under weak (1, 3) homotopy (Corollary 4.1).