Limits of equilibrium states for coupled weakly interacting systems. Application to the measure of maximal entropy
Renaud Leplaideur
TL;DR
The paper analyzes metastability in coupled weakly interacting systems via symbolic dynamics and thermodynamic formalism. By representing two independent subshifts of finite type connected through a shrinking coupling hole, it derives how the global equilibrium state converges to a convex combination of the independent equilibria, with weights determined by dwell-time parameters encoded in θ. The authors develop inducing schemes, transfer-operator methods, and extensions of eigenfunctions to compare local and global equilibria, obtaining precise limiting distributions for both the conformal measure and the eigenfunction, as well as the measure of maximal entropy in a geometric setting. A key contribution is showing that, under two different hole-reduction schemes, the limit is either (1/2)(μ_A+μ_D) or (1/(1+θ))(θ μ_A + μ_D), highlighting robust metastable behavior and enabling a bridge to geometrical systems via a conjugacy that yields convergence of the measure of maximal entropy to the average of the two component measures. These results deepen the understanding of how small couplings shape long-term statistical behavior in dynamical systems and provide tools for extending the analysis to more complex, multi-component arrangements.
Abstract
We study metastability for symbolic dynamic. We prove that for a global system given by two independent sub-systems linked by a hole, and for a Lipschitz continuous potential, the global equilibrium state converges, as the hole shrinks, to a convex combination of the two independent equilibria in each component. Two kinds of convergence occur, depending on the assumptions on how long an orbit has to stay in each well. As a by-product, we show that this can be applied to a geometrical system inspired from [11] and for the measure of maximal entropy.
