Conditioned stochastic stability of equilibrium states on uniformly hyperbolic sets
Bernat Bassols Cornudella, Matheus M. Castro
TL;DR
The paper develops a rigorous framework for conditioned stochastic stability of equilibrium states on uniformly hyperbolic sets by studying quasi-ergodic measures of small-noise perturbations. It combines perturbative transfer-operator theory on anisotropic Banach spaces with Conley-style dynamical filtrations to produce local and global results, proving convergence to equilibrium states associated with the modified potential $\psi=\phi-\log|\det DT|_{E^u}|$. The authors provide constructive methods to obtain quasi-ergodic measures from dominant eigenfunctions and illustrate the theory on the Hénon repeller and Arnold’s cat map, thus linking transient chaos statistics to thermodynamic formalism. This yields a robust, spectrally grounded approach to characterizing natural measures on repellers and offers practical avenues for data-driven approximation of these measures. The global extension to Axiom A systems with multiple basic sets enhances the utility of the framework for complex dynamical scenarios with competing invariant sets.
Abstract
We establish the conditioned stochastic stability of equilibrium states for Hölder potentials on uniformly hyperbolic sets. While standard stochastic stability characterises measures on attractors, we analyse the statistics of transient dynamics on non-attracting sets by conditioning small random perturbations of the dynamics to not escape from our regions of interest. We prove that as the noise intensity vanishes, the quasi-ergodic measure of the $e^φ$-weighted process generated by $\e$-small random perturbations of the deterministic dynamics converges to the unique equilibrium state associated with the potential $φ- \log \left|\det \left. D T\right|_{E^u}\right|$. The results are obtained via perturbative spectral analysis of transfer operators acting on anisotropic Banach spaces and topological hyperbolic dynamics arguments. Furthermore, we extend this framework globally to Axiom A diffeomorphisms with multiple basic sets using dynamical filtrations. This work provides a rigorous characterisation of natural measures on uniformly hyperbolic repellers, which are fundamental in the context of transient chaos.
