Continuity of the drift in groups acting on strongly hyperbolic spaces

Abstract

The Avalanche principle, in its original setting, together with large deviations yields a systematic way of proving the continuity of the Lyapunov exponent. In this text we present a geometric version of the Avalanche Principle in the context of hyperbolic spaces, which will extend the usage of these techniques to study the drift in such spaces. This continuity criteria applies not only to the drift but also to the limit point of the process itself. We apply this abstract result to derive continuity of the drift for Markov processes in strongly hyperbolic spaces.