TY - JOUR A1 - Baptista, Murilo da Silva A1 - Grebogi, Celso A1 - Koberle, Roland T1 - Dynamically multilayered visual system of the multifractal fly JF - Physical review letters Y1 - 2006 U6 - https://doi.org/10.1103/PhysRevLett.97.178102 SN - 0031-9007 VL - 97 IS - 17 PB - American Physical Society CY - College Park ER - TY - JOUR A1 - Feudel, Fred A1 - Witt, Annette A1 - Gellert, Marcus A1 - Kurths, Jürgen A1 - Grebogi, Celso A1 - Sanjuan, Miguel Angel Fernandez T1 - Intersections of stable and unstable manifolds : the skeleton of Lagrangian chaos N2 - We study Hamiltonian chaos generated by the dynamics of passive tracers moving in a two-dimensional fluid flow and describe the complex structure formed in a chaotic layer that separates a vortex region from the shear flow. The stable and unstable manifolds of unstable periodic orbits are computed. It is shown that their intersections in the Poincare map as an invariant set of homoclinic points constitute the backbone of the chaotic layer. Special attention is paid to the finite time properties of the chaotic layer. In particular, finite time Lyapunov exponents are computed and a scaling law of the variance of their distribution is derived. Additionally, the box counting dimension as an effective dimension to characterize the fractal properties of the layer is estimated for different duration times of simulation. Its behavior in the asymptotic time limit is discussed. By computing the Lyapunov exponents and by applying methods of symbolic dynamics, the formation of the layer as a function of the external forcing strength, which in turn represents the perturbation of the originally integrable system, is characterized. In particular, it is shown that the capture of KAM tori by the layer has a remarkable influence on the averaged Lyapunov exponents. (C) 2004 Elsevier Ltd. All rights reserved Y1 - 2005 ER - TY - JOUR A1 - Viana, Ricardo L. A1 - Barbosa, José R. R. A1 - Grebogi, Celso T1 - Unstable dimension variability and codimension-one bifurcations of two-dimensional maps N2 - Unstable dimension variability is a mechanism whereby an invariant set of a dynamical system, like a chaotic attractor or a strange saddle, loses hyperbolicity in a severe way, with serious consequences on the shadowability properties of numerically generated trajectories. In dynamical systems possessing a variable parameter, this phenomenon can be triggered by the bifurcation of an unstable periodic orbit. This Letter aims at discussing the possible types of codimension-one bifurcations leading to unstable dimension variability in a two-dimensional map, presenting illustrative examples and displaying numerical evidences of this fact by computing finite-time Lyapunov exponents. (C) 2004 Elsevier B.V. All rights reserved Y1 - 2004 SN - 0375-9601 ER - TY - JOUR A1 - Lai, Ying Cheng A1 - Nagai, Y. A1 - Grebogi, Celso T1 - Characterization of the natural measure by unstable periodic orbits in chaotic attractors Y1 - 1997 ER - TY - JOUR A1 - Hunt, Brain R. A1 - Grebogi, Celso A1 - Barreto, Ernest A1 - Yorke, James A. T1 - From high dimensional chaos to stable periodic orbits : the structure of parameter space Y1 - 1997 ER - TY - JOUR A1 - Kraut, Suso A1 - Feudel, Ulrike A1 - Grebogi, Celso T1 - Preference of attractors in noisy multistable systems Y1 - 1999 ER -