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Related papers: Quantifying chaos using Lagrangian descriptors

200 papers

We propose Lagrangian Descriptors (LDs) as a diagnostic framework for evaluating neural network models of Hamiltonian systems beyond conventional trajectory-based metrics. Standard error measures quantify short-term predictive accuracy but…

Machine Learning · Computer Science 2026-04-02 Abrari Noor Hasmi , Haralampos Hatzikirou , Hadi Susanto

Observability can determine which recorded variables of a given system are optimal for discriminating its different states. Quantifying observability requires knowledge of the equations governing the dynamics. These equations are often…

Adaptation and Self-Organizing Systems · Physics 2020-10-28 Christopher E. Gonzalez , Claudia Lainscsek , Terrence J. Sejnowski , Christophe Letellier

The chaotic or ordered character of orbits in galactic models is an important issue, since it can influence dynamical evolution. This distinction can be achieved with the help of the Smaller Alingment Index - (SALI). We describe here…

Astrophysics · Physics 2009-11-11 T. Manos , E. Athanassoula

A very important issue in the area of galactic dynamics is the detection of chaotic and ordered motion inside galaxies. In order to achieve this target, we use the Smaller ALignment Index (SALI) method, which is a very suitable tool for…

Astrophysics · Physics 2007-05-23 T. Manos , E. Athanassoula

The dynamical evolution of barred galaxies depends crucially on the fraction and their spacial distribution of chaotic orbits in them. In order to distinguish between the two kinds of orbits, we use the Smaller Alignment Index (SALI)…

Astrophysics · Physics 2007-05-23 T. Manos , E. Athanassoula

In this paper we demonstrate that the phase space arclength of a trajectory, quantified by the time-averaged Lagrangian descriptor, is a robust and self-contained chaos indicator. By invoking Birkhoff's Ergodic Partition Theorem, we show…

Chaotic Dynamics · Physics 2026-02-10 Javier Jiménez-López , V. J. García-Garrido

We investigate localization phenomena and stability properties of quasiperiodic oscillations in $N$ degree of freedom Hamiltonian systems and $N$ coupled symplectic maps. In particular, we study an example of a parametrically driven…

Chaotic Dynamics · Physics 2015-05-13 T. Bountis , T. Manos , H. Christodoulidi

Lagrangian Descriptors (LDs) are scalar quantities able to reveal separatrices, manifolds of hyperbolic saddles, and chaotic seas of dynamical systems. A popular version of the LDs consists in computing the arc-length of trajectories over a…

Dynamical Systems · Mathematics 2022-10-25 Pedenon-Orlanducci Remi , Carletti Timoteo , Lemaitre Anne , Daquin Jerome

The correlation between level velocities and eigenfunction intensities provides a new way of exploring phase space localization in quantized non-integrable systems. It can also serve as a measure of deviations from ergodicity due to quantum…

Chaotic Dynamics · Physics 2009-10-31 Arul Lakshminarayan , Nicholas R. Cerruti , Steven Tomsovic

The efficient detection of chaotic behavior in orbits of a complex dynamical system is an active domain of research. Several indicators have been proposed in the past, and new ones have recently been developed in view of improving the…

Dynamical Systems · Mathematics 2023-07-05 A. Bazzani , M. Giovannozzi , C. E. Montanari , G. Turchetti

We present our recent contributions to the theory of Lagrangian descriptors for discriminating ordered and deterministic chaotic trajectories. The class of Lagrangian Descriptors we are dealing with is based on the Euclidean length of the…

Chaotic Dynamics · Physics 2023-09-20 Jerome Daquin

Magnetic field line chaos occurs under the presence of non-axisymmetric perturbations of an axisymmetric equilibrium and is manifested by the destruction of smooth flux surfaces formed by the field lines. These perturbations also render the…

A type of chaos called laminar chaos was found in singularly perturbed dynamical systems with periodically [Phys. Rev. Lett. 120, 084102 (2018)] and quasiperiodically [Phys. Rev. E 107, 014205 (2023)] time-varying delay. Compared to…

Chaotic Dynamics · Physics 2025-08-29 David Müller-Bender , Rahil N. Valani

To determine the regular or chaotic nature of the orbits in dynamical systems can be quite an issue. In this article, following Vozikis et al. (2000), we propose a new tool, namely, the Power Spectrum Indicator (PSI), $\psi^2$, that enables…

Chaotic Dynamics · Physics 2018-08-02 Christos Vozikis , Konstantinos Kleidis , Stavros Papaioannou

We investigate the long-term dynamical structure of low Earth orbits (LEOs) using the Smaller Alignment Index (SALI), a fast numerical indicator of chaos, within a closed-form averaged model that incorporates the effects of solar radiation…

Chaotic Dynamics · Physics 2026-05-26 Cassandra Barbis , Jerome Daquin , Elisa Maria Alessi , Charalampos Skokos

A 3D dynamical model with a quasi-homogeneous core and a disk component is used for the chaos control in the central parts of elliptical galaxy. Numerical experiments in the 2D system show a very complicated phase plane with a large chaotic…

Astrophysics of Galaxies · Physics 2018-03-14 Euaggelos E. Zotos

As originally formulated, the Generalized Alignment Index (GALI) method of chaos detection has so far been applied to distinguish quasiperiodic from chaotic motion in conservative nonlinear dynamical systems. In this paper we extend its…

Chaotic Dynamics · Physics 2013-10-17 T. Manos , Ch. Skokos , Ch. Antonopoulos

The ability of the Smaller Alignment Index (SALI) to distinguish chaotic from ordered motion, has been demonstrated recently in several publications.\cite{Sk01,GRACM} Basically it is observed that in chaotic regions the SALI goes to zero…

Chaotic Dynamics · Physics 2016-09-08 Ch. Skokos , Ch. Antonopoulos , T. C. Bountis , M. N. Vrahatis

We study the regular or chaotic character of orbits in a 3D dynamical model, describing a triaxial galaxy surrounded by a spherical dark halo component. Our numerical experiments suggest that the percentage of chaotic orbits decreases…

Astrophysics of Galaxies · Physics 2012-04-10 Nicolaos D. Caranicolas , Euaggelos E. Zotos

We explore the nature of orbits of stars moving in the meridional plane $(R,z)$ of an axially symmetric galactic model with a disk, a spherical nucleus, and a flat biaxial dark matter halo component. In particular, we study the influence of…

Astrophysics of Galaxies · Physics 2014-04-17 Euaggelos E. Zotos