Pair-factorized steady states on arbitrary graphs

TL;DR

This paper investigates the inverse problem of identifying hopping rates in stochastic mass transport models that lead to a given pair-factorized steady state on arbitrary graphs, revealing classes of functions and phase behaviors.

Contribution

It introduces a class of hopping functions that produce the same steady state and explores phase structures and reductions to zero-range processes.

Findings

Defined a class of hopping functions maintaining the steady state

Analyzed phase structure in anisotropic two-dimensional cases

Mapped the problem to solvable zero-range processes

Abstract

Stochastic mass transport models are usually described by specifying hopping rates of particles between sites of a given lattice, and the goal is to predict the existence and properties of the steady state. Here we ask the reverse question: given a stationary state that factorizes over links (pairs of sites) of an arbitrary connected graph, what are possible hopping rates that converge to this state? We define a class of hopping functions which lead to the same steady state and guarantee current conservation but may differ by the induced current strength. For the special case of anisotropic hopping in two dimensions we discuss some aspects of the phase structure. We also show how this case can be traced back to an effective zero-range process in one dimension which is solvable for a large class of hopping functions.