Finite precision and transient behavior

Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics, 2000

For a family of logisticlike maps, we investigate the rate of convergence to the critical attractor when an ensemble of initial conditions is uniformly spread over the entire phase space. We found that the phase-space volume occupied by the ensemble W(t) depicts a power-law decay with log-periodic oscillations reflecting the multifractal character of the critical attractor. We explore the parametric dependence of the power-law exponent and the amplitude of the log-periodic oscillations with the attractor's fractal dimension governed by the inflection of the map near its extremal point. Further, we investigate the temporal evolution of W(t) for the circle map whose critical attractor is dense. In this case, we found W(t) to exhibit a rich pattern with a slow logarithmic decay of the lower bounds. These results are discussed in the context of nonextensive Tsallis entropies.

Phys Rev E, 2000

For a family of logistic-like maps, we investigate the rate of convergence to the critical attractor when an ensemble of initial conditions is uniformly spread over the entire phase space. We found that the phase space volume occupied by the ensemble W(t) depicts a power-law decay with log-periodic oscillations reflecting the multifractal character of the critical attractor. We explore the parametric dependence of the power-law exponent and the amplitude of the log-periodic oscillations with the attractor's fractal dimension governed by the inflexion of the map near its extremal point. Further, we investigate the temporal evolution of W(t) for the circle map whose critical attractor is dense. In this case, we found W(t) to exhibit a rich pattern with a slow logarithmic decay of the lower bounds. These results are discussed in the context of nonextensive Tsallis entropies.

Physical review, 1985

%e present a theory of attractors on finite sets which is applicable to finite-state systems such as computing structures and other systems which display a hierarchy of organizations with a discrete time evolution. Because computing with attractive fixed points can lead to reliable behavior [B. A. Huberman and T. Hogg, Phys. Rev. Lett. 52, 1048 (1984)], the theory deals with dissipative process- es, i.e. , those which contract volumes in phase space. The stability of such systems is quantified and analytic expressions are obtained for the appropriate indices in some limiting cases. It is also shown that trees with ultrametric topologies provide the natural language for the'se systems. The theory is extended to include several practical constraints, and connections are made with experimental quan- tities which can be measured in particular architectures.

Chaos: An Interdisciplinary Journal of Nonlinear Science, 2008

The motion of a spinning football brings forth the possible existence of a whole class of finite dynamical systems where there may be non-denumerably infinite number of fixed points. They defy the very traditional meaning of the fixed point that a point on the fixed point in the phase space should remain there forever, for, a fixed point can evolve as well! Under such considerations one can argue that a free-kicked football should be non-chaotic.

Bulletin of the American Mathematical Society, 1988

Communications in Mathematical Physics, 1981

The "strange attractors" plotted by computers and seen in physical experiments do not necessarily have an open basin of attraction. In view of this we study a new definition of attractors based on ideas of Conley. We argue that the attractors observed in the presence of small random perturbations correspond to this new definition.

Dynamical Systems, 2018

Recurrence determinism, one of the fundamental characteristics of recurrence quantification analysis, measures predictability of a trajectory of a dynamical system. It is tightly connected with the conditional probability that, given a recurrence, following states of the trajectory will be recurrences. In this paper we study recurrence determinism of interval dynamical systems. We show that recurrence determinism distinguishes three main types of ω-limit sets of zero entropy maps: finite, solenoidal without non-separable points, and solenoidal with non-separable points. As a corollary we obtain characterizations of strongly non-chaotic and Li-Yorke (non-)chaotic interval maps via recurrence determinism. For strongly non-chaotic maps, recurrence determinism is always equal to one. Li-Yorke non-chaotic interval maps are those for which recurrence determinism is always positive. Finally, Li-Yorke chaos implies the existence of a Cantor set of points with zero determinism.

Communications in Nonlinear Science and Numerical Simulation, 2011

The effect of numerical precision on the mean distance and on the mean coalescence time between trajectories of two random maps was investigated. It was shown that mean coalescence time between trajectories can be used to characterize regions of the phase space of the maps. The mean coalescence time between trajectories scales as a power law as a function of the numerical precision of the calculations in the contracting and transitions regions of the maps. In the contracting regions the exponent of the power law is approximately one for both maps and it is approximately two in the transition regions for both maps. In the chaotic regions, the mean coalescence time between trajectories scales as an exponential law as a function of the numerical precision of the calculations for the maps. For both maps the exponents are of the same order of magnitude in the chaotic regions.

Journal of Statistical Physics, 1983

We investigate asymptotic properties of certain discrete-time dynamical systems in two and three dimensions with solenoidal attractor. It is proved that the asymptotic measures, relevant for the generalized version of the ergodic theorem, all derive from one Haar measure. KEY WORDS: Long time behavior of dissipative systems; asymptotic measures on strange attractors; correlation functions; Smale's solenoid.

Physical Review E, 2009

The topological structure of basin boundaries plays a fundamental role in the sensitivity to the final state in chaotic dynamical systems. Herewith we present a study on the dynamics of dissipative systems close to the Hamiltonian limit, emphasising the increasing number of periodic attractors, and on the structural changes in their basin boundaries as the dissipation approaches zero. We show numerically that a power law with nontrivial exponent describes the growth of the total number of periodic attractors as the damping is decreased. We also establish that for small scales the dynamics is governed by effective dynamical invariants, whose measure depends not only on the region of the phase space, but also on the scale under consideration. Therefore, our results show that the concept of effective invariants is also relevant for dissipative systems. PACS numbers: 05.45.Ac 61.43.Hv I.