English

Holomorphic quadratic differentials on graphs and the chromatic polynomial

Combinatorics 2018-03-02 v1

Abstract

We study "holomorphic quadratic differentials" on graphs. We relate them to the reactive power in an LC circuit, and also to the chromatic polynomial of a graph. Specifically, we show that the chromatic polynomial χ\chi of a graph GG, at negative integer values, can be evaluated as the degree of a certain rational mapping, arising from the defining equations for a holomorphic quadratic differential. This allows us to give an explicit integral expression for χ(k)\chi(-k).

Keywords

Cite

@article{arxiv.1803.00115,
  title  = {Holomorphic quadratic differentials on graphs and the chromatic polynomial},
  author = {Richard Kenyon and Wai Yeung Lam},
  journal= {arXiv preprint arXiv:1803.00115},
  year   = {2018}
}
R2 v1 2026-06-23T00:37:29.280Z