2008/03/20 by Boris Kalinin, Kalinin, Boris, Anatole Katok +3
Mathematics · Physics and Astronomy · #37C40 #37C85 #37D25 #Classical Analysis and ODEs (math.CA) #Dynamical Systems (math.DS) #FOS: Mathematics #Mathematical Dynamics and Fractals #Quantum chaos and dynamical systems
paper · pdf · doi:10.48550/arxiv.0803.3094
openalex publication_date 2008/03/20 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We consider an ergodic invariant measure μ for a smooth action of Zk, k ≥ 2, on a (k+1)-dimensional manifold or for a locally free smooth action of Rk, k ≥ 2 on a (2k+1)-dimensional manifold. We prove that if μ is hyperbolic with the Lyapunov hyperplanes in general position and if one element of the action has positive entropy, then μ is absolutely continuous. The main ingredient is absolute continuity of conditional measures on Lyapunov foliations which holds for a more general class of smooth actions of higher rank abelian groups.