Density of Positive Lyapunov Exponents for Sl(2,r)-cocycles
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چکیده
1. Under suitable smoothness assumptions, quasiperiodicity, and hence the absence of any kind of hyperbolicity, is non-negligible in a measure-theoretical sense [Kol] (under suitable smoothness assumptions). 2. In low regularity (C), failure of non-uniform hyperbolicity (here nonuniform hyperbolicity can be understood as positivity of the metric entropy) is a fairly robust phenomenon in the topological sense [B].
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تاریخ انتشار 2011