Konstantin Khanin, Sasa Kocic Hausdorff dimension of invariant measure of circle diffeomorphisms with breaks (460K, pdf) ABSTRACT. We prove that, for almost all irrational rho in (0,1), Hausdorff dimension of invariant measure of circle diffeomorphisms with breaks, with rotation number rho, is zero. This result cannot be extended to all irrational rotation numbers.