Self-similar groups and permutational bimodules are used to study combinatorics and symbolic dynamics of expanding self-coverings. We describe functors between the category of contracting self-similar groups and the category of expanding self-coverings (with appropriate morphisms). These functors transform some questions in dynamical systems to questions in algebra. As examples we show how some...

In this paper we consider space-times containing matter expanding or contracting according to a time-dependent scale factor. Cosmologies with vanishing, positive or negative cosmological constant are considered. In the case of vanishing or negative cosmological constant open and closed spatial surfaces are solutions while in the case of positive cosmological constant only closed surfaces exist....

Self-similar group actions (or self-similar groups) have proved to be interesting mathematical objects from the point of view of group theory and from the point of view of many other fields of mathematics (operator algebras, holomorphic dynamics, automata theory, etc). See the works [BGN02, GNS00, Gri00, Sid98, BG00, Nek02a], where different aspects of self-similar groups are studied. An import...

The data from two experiments, both using stimuli simulating orthographically rotating surfaces, are presented, with the primary variable of interest being whether the magnitude of the simulated gradient was from expanding vs. contracting motion. One experiment asked observers to report the apparent slant of the rotating surface, using a gauge figure. The other experiment asked observers to rep...

We consider partially hyperbolic diieomorphisms preserving a splitting of the tangent bundle into a strong-unstable subbundle E uu (uniformly expanding) and a subbundle E c , dominated by E uu. We prove that if the central direction E c is mostly contracting for the diieomorphism (negative Lyapunov exponents), then the ergodic Gibbs u-states are the Sinai-Ruelle-Bowen measures, there are nitely...