English

Planar Graphical Models which are Easy

Statistical Mechanics 2015-05-13 v5 Disordered Systems and Neural Networks Computational Complexity Information Theory Mathematical Physics math.IT math.MP

Abstract

We describe a rich family of binary variables statistical mechanics models on a given planar graph which are equivalent to Gaussian Grassmann Graphical models (free fermions) defined on the same graph. Calculation of the partition function (weighted counting) for such a model is easy (of polynomial complexity) as reducible to evaluation of a Pfaffian of a matrix of size equal to twice the number of edges in the graph. In particular, this approach touches upon Holographic Algorithms of Valiant and utilizes the Gauge Transformations discussed in our previous works.

Keywords

Cite

@article{arxiv.0902.0320,
  title  = {Planar Graphical Models which are Easy},
  author = {Vladimir Y. Chernyak and Michael Chertkov},
  journal= {arXiv preprint arXiv:0902.0320},
  year   = {2015}
}

Comments

27 pages, 11 figures; misprints corrected

R2 v1 2026-06-21T12:07:09.019Z