English

One-cocycle invariants for closed braids

Geometric Topology 2018-04-11 v1

Abstract

We introduce new polynomial isotopy invariants for closed braids. They are constructed as polynomial valued {\em Gauss diagram 1-cocycles} evaluated on the full rotation of the closed braid β^\hat \beta around the core of the corresponding solid torus. They can be calculated with polynomial complexity with respect to the braid length and their derivatives evaluated at x=1x=1 are finite type invariants of closed braids. Let the solid torus V be standardly embedded in the 3-sphere and let L be the core of the complementary solid torus S3VS^3\setminus V. We give examples which show that a natural refinement of our invariants can detect (even with linear complexity with respect to the braid length if the number of strands is fixed, and with quadratic complexity if it is not fixed) the non-invertibility of the 2-component link β^LS3\hat \beta \cup L\hookrightarrow S^3, what quantum invariants fail to do.

Keywords

Cite

@article{arxiv.1804.03549,
  title  = {One-cocycle invariants for closed braids},
  author = {Thomas Fiedler},
  journal= {arXiv preprint arXiv:1804.03549},
  year   = {2018}
}

Comments

44 pages, 29 figures. arXiv admin note: text overlap with arXiv:math/0606443

R2 v1 2026-06-23T01:19:24.087Z