English

Average signature and 4-genus of 2-bridge knots

Geometric Topology 2024-06-26 v1

Abstract

We show that the average or expected absolute value of the signatures of all 2-bridge knots with crossing number cc approaches 2c/π\sqrt{{2c}/{\pi}}. Baader, Kjuchukova, Lewark, Misev, and Ray consider a model for 2-bridge knot diagrams indexed by diagrammatic crossing number nn and show that the average 4-genus is sublinear in nn. We build upon this result in two ways to obtain an upper bound for the average 4-genus of a 2-bridge knot: our model is indexed by crossing number cc and gives a specific sublinear upper bound of 9.75c/logc9.75c/\log c.

Keywords

Cite

@article{arxiv.2406.17738,
  title  = {Average signature and 4-genus of 2-bridge knots},
  author = {Moshe Cohen and Adam M. Lowrance and Neal Madras and Steven Raanes},
  journal= {arXiv preprint arXiv:2406.17738},
  year   = {2024}
}

Comments

33 pages, 10 figures