English

Computing Ribbon Obstructions for Colored Knots

Geometric Topology 2021-07-09 v2

Abstract

Kjuchukova's Ξp\Xi_p invariant gives a ribbon obstruction for Fox pp-colored knots. The invariant is derived from dihedral branched covers of 4-manifolds, and is needed to calculate the signatures of these covers, when singularities on the branching sets are present. In this note, we give an algorithm for evaluating Ξp\Xi_p from a colored knot diagram, and compute a couple of examples.

Cite

@article{arxiv.1812.09553,
  title  = {Computing Ribbon Obstructions for Colored Knots},
  author = {Patricia Cahn and Alexandra Kjuchukova},
  journal= {arXiv preprint arXiv:1812.09553},
  year   = {2021}
}

Comments

14 pages. 0 footnotes. Changes to exposition and new example. To appear in Fundamenta Mathematicae. Originally part of arXiv:1710.11562

R2 v1 2026-06-23T06:54:33.208Z