A note on the asymptotics of perturbed expanding maps.
We investigate the properties of the entropy and conditional entropy of measurable partitions of unity in the space of essentially bounded functions defined on a Lebesgue probability space.
We give a simple direct proof of the polar decomposition for separated linear maps in pseudo-Euclidean geometry.
We consider continuous -cocycles over a minimal homeomorphism of a compact set of finite dimension. We show that the generic cocycle either is uniformly hyperbolic or has uniform subexponential growth.
We consider volume-preserving perturbations of the time-one map of the geodesic flow of a compact surface with negative curvature. We show that if the Liouville measure has Lebesgue disintegration along the center foliation then the perturbation is itself the time-one map of a smooth volume-preserving flow, and that otherwise the disintegration is necessarily atomic.