%0 Journal Article %T Hyperbolic Invariant Sets With Positive Measures %A Zhihong Xia %J Mathematics %D 2005 %I arXiv %X If a $C^{1 + a}$, $a >0$, volume-preserving diffeomorphism on a compact manifold has a hyperbolic invariant set with positive volume, then the map is Anosov. We also give a direct proof of ergodicity of volume-preserving $CC^{1+a}$, $a>0$, Anosov diffeomorphism without the usual Hopf argument. %U http://arxiv.org/abs/math/0503437v2