
ВИДЕОТЕКА 
Конференция «Hyperbolic Dynamics and Structural Stability», посвященная 85летию Д. В. Аносова



Mingled hyperbolicities: Restricted variational principles L. J. Díaz^{} ^{} Pontifical Catholic University of Rio de Janeiro 

Аннотация: We quantify ergodically the lack of hyperbolicity in transitive diffeomorphisms with onedimensional nonhyperbolic center. For that, we investigate step skew products whose fiber dynamics are circle diffeomorphisms. Such dynamics captures the key mechanisms of the dynamics of robustly transitive and nonhyperbolic maps with onedimensional center. It also arises from the projective action of certain A key feature of these systems is the coexistence of saddles of different types of hyperbolicity, described in terms of fibercontracting and expanding regions which are mingled by the dynamics. It gives also rise to nonhyperbolic ergodic measures characterized in terms of a zero Lyapunov exponent in the circlefiber direction. Some of those measures have positive entropy. We describe the topological entropy of each level set of points with fiberLyapunov exponent The talk is based on a joints works with K. Gelfert (UFRJ, Brazil) and M. Rams (IMPAN, Poland). Язык доклада: английский 