Rapid mixing for compact group extensions of hyperbolic flows
Mark Pollicott, Daofei Zhang
TL;DR
The article proves that compact group extensions f_t of hyperbolic flows g_t exhibit rapid mixing with respect to the natural local product measure when a Diophantine condition on the Brin holonomy group holds, with decay faster than any polynomial for Hölder observables. The authors build a symbolic model via Markov partitions and skew products, and obtain a Dolgopyat-type estimate for the associated transfer operators across irreducible representations, enabling analytic continuation of Laplace transforms of correlations. This yields both rapid decay of correlations for the extension flow and superpolynomial equidistribution of holonomies around closed orbits, with frame flows in negative curvature serving as key applications. In particular, for frame flows with suitable Brin-group density (e.g., many negative curvature settings in dimension d ≥ 4), rapid mixing and superpolynomial equidistribution hold, reinforcing the statistical understanding of holonomy dynamics in geometric settings.
Abstract
In this article, we give explicit conditions for compact group extensions of hyperbolic flows (including geodesic flows on negatively curved manifolds) to exhibit quantifiable rates of mixing (or decay of correlations) with respect to the natural probability measures, which are locally the product of a Gibbs measure for a Hölder potential and the Haar measure. More precisely, we show that the mixing rate with respect to Hölder functions will be faster than any given polynomial (i.e., rapid mixing). We also give error estimates on the equidistribution of the holonomy around closed orbits. In particular, these results apply to some frame flows for manifolds with negative sectional curvatures.
