English

Crossing Number is Hard for Kernelization

Computational Complexity 2016-02-19 v2 Combinatorics

Abstract

The graph crossing number problem, cr(G)<=k, asks for a drawing of a graph G in the plane with at most k edge crossings. Although this problem is in general notoriously difficult, it is fixed- parameter tractable for the parameter k [Grohe]. This suggests a closely related question of whether this problem has a polynomial kernel, meaning whether every instance of cr(G)<=k can be in polynomial time reduced to an equivalent instance of size polynomial in k (and independent of |G|). We answer this question in the negative. Along the proof we show that the tile crossing number problem of twisted planar tiles is NP-hard, which has been an open problem for some time, too, and then employ the complexity technique of cross-composition. Our result holds already for the special case of graphs obtained from planar graphs by adding one edge.

Keywords

Cite

@article{arxiv.1512.02379,
  title  = {Crossing Number is Hard for Kernelization},
  author = {Petr Hliněný and Marek Derňár},
  journal= {arXiv preprint arXiv:1512.02379},
  year   = {2016}
}
R2 v1 2026-06-22T12:03:59.770Z