Nesting statistics in the $O(n)$ loop model on random maps of arbitrary topologies

TL;DR

This paper extends the analysis of nesting statistics in the $O(n)$ loop model on random maps to arbitrary topologies, using topological recursion and characterizing behavior at critical points.

Contribution

It generalizes previous work to all topologies and provides explicit computations and critical behavior analysis for the $O(n)$ loop model on random maps.

Findings

Explicit generating series for maps with fixed topology and nesting graphs

Behavior characterization at criticality in dense and dilute phases

Applicability to models with bending energy on triangulations

Abstract

We pursue the analysis of nesting statistics in the $O(n)$ loop model on random maps, initiated for maps with the topology of disks and cylinders in math-ph/1605.02239, here for arbitrary topologies. For this purpose we rely on the topological recursion results of math-ph/0910.5896 and math-ph/1303.5808 for the enumeration of maps in the $O(n)$ model. We characterize the generating series of maps of genus $g$ with $k'$ marked points and $k$ boundaries and realizing a fixed nesting graph. These generating series are amenable to explicit computations in the loop model with bending energy on triangulations, and we characterize their behavior at criticality in the dense and in the dilute phase.