# A theory of non-equilibrium local search on random satisfaction problems

## TL;DR

This paper develops a new theoretical framework using cavity master equations to predict the dynamics of non-equilibrium local search algorithms solving random k-satisfiability problems, outperforming traditional equilibrium-based models.

## Contribution

It introduces a systematic non-equilibrium theory for local search algorithms on satisfiability problems, validated on random 3-satisfiability instances.

## Key findings

- Accurately predicts the solution process away from phase boundaries.
- Qualitatively captures the location of the algorithm phase boundary.
- Outperforms equilibrium Gibbs state predictions in non-equilibrium regimes.

## Abstract

We study local search algorithms to solve instances of the random $k$-satisfiabi lity problem, equivalent to finding (if they exist) zero-energy ground states of statistical models with disorder on random hypergraphs. It is well known that the best such algorithms are akin to non-equilibrium processes in a high-dimensional space. In particular, algorithms known as focused, and which do not obey detailed balance, outperform simulated annealing and related methods in the task of finding the solution to a complex satisfiability problem, that is to find (exactly or approximately) the minimum in a complex energy landscape. A physical question of interest is if the dynamics of these processes can be well predicted by the well-developed theory of equilibrium Gibbs states. While it has been known empirically for some time that this is not the case, an alternative systematic theory that does so has been lacking. In this paper we introduce such a theory based on the recently developed technique of cavity master equations and test it on the paradigmatic random $3$-satisfiability problem. Our theory predicts the solution process very accurately away from the algorithm phase boundary and also predicts the qualitative form of this boundary.