Parameterizing the Permanent: Hardness for -minor-free graphs
arXiv:2108.12879
Abstract
In the 1960s, statistical physicists discovered a fascinating algorithm for counting perfect matchings in planar graphs. Valiant later showed that the same problem is #P-hard for general graphs. Since then, the algorithm for planar graphs was extended to bounded-genus graphs, to graphs excluding or , and more generally, to any graph class excluding a fixed minor that can be drawn in the plane with a single crossing. This stirred up hopes that counting perfect matchings might be polynomial-time solvable for graph classes excluding any fixed minor . Alas, in this paper, we show #P-hardness for -minor-free graphs by a simple and self-contained argument.
12 pages