Birkhoff averages and rotational invariant circles for area-preserving maps

E Sander, JD Meiss - Physica D: Nonlinear Phenomena, 2020 - Elsevier
Rotational invariant circles of area-preserving maps are an important and well-studied
example of KAM tori. John Greene conjectured that the locally most robust rotational circles …

Birkhoff averages and the breakdown of invariant tori in volume-preserving maps

JD Meiss, E Sander - Physica D: Nonlinear Phenomena, 2021 - Elsevier
In this paper, we develop numerical methods based on the weighted Birkhoff average for
studying two-dimensional invariant tori for volume-preserving maps. The methods do not …

Distinguishing between regular and chaotic orbits of flows by the weighted Birkhoff average

N Duignan, JD Meiss - Physica D: Nonlinear Phenomena, 2023 - Elsevier
This paper investigates the utility of the weighted Birkhoff average (WBA) for distinguishing
between regular and chaotic orbits of flows, extending previous results that applied the WBA …

Resonance and weak chaos in quasiperiodically-forced circle maps

JD Meiss, E Sander - … in Nonlinear Science and Numerical Simulation, 2024 - Elsevier
In this paper, we distinguish between four categories of dynamics for quasiperiodically-
forced (QPF) circle maps: resonant and incommensurate regular dynamics, and strongly and …

Rotation Vectors for Torus Maps by the Weighted Birkhoff Average

E Sander, JD Meiss - arXiv preprint arXiv:2310.11600, 2023 - arxiv.org
In this paper, we focus on distinguishing between the types of dynamical behavior that occur
for typical one-and two-dimensional torus maps, in particular without the assumption of …

Weighted Birkhoff averages and the parameterization method

D Blessing, JD Mireles James - SIAM Journal on Applied Dynamical Systems, 2024 - SIAM
This work provides a systematic recipe for computing accurate high order Fourier
expansions of quasiperiodic invariant circles (and systems of such circles) in area …

Efficient and reliable algorithms for the computation of non-twist invariant circles

A González, À Haro, R de la Llave - Foundations of Computational …, 2022 - Springer
This paper presents a methodology to study non-twist invariant circles and their bifurcations
for area preserving maps, which is supported on the theoretical framework developed in …

Reconstructing dynamical systems as zero-noise limits

S Das - arXiv preprint arXiv:2407.16673, 2024 - arxiv.org
A dynamical system may be defined by a simple transition law-such as a map or a vector
field. The objective of most learning techniques is to reconstruct this dynamic transition law …

Discrete-time dynamics, step-skew products, and pipe-flows

S Das - arXiv preprint arXiv:2409.02318, 2024 - arxiv.org
A discrete-time deterministic dynamical system is governed at every step by a
predetermined law. However the dynamics can lead to many complexities in the phase …

Fast-ion transport in quasisymmetric equilibria in the presence of a resonant Alfvénic perturbation

EJ Paul, HE Mynick, A Bhattacharjee - Journal of Plasma Physics, 2023 - cambridge.org
Significant progress has been made in designing magnetic fields that provide excellent
confinement of the guiding-centre trajectories of alpha particles using quasisymmetry (QS) …