Chaos, ergodic convergence, and fractal instability for a thermostated canonical harmonic oscillator.

The Equivalence of Dissipation from Gibbs' Entropy Production with Phase-Volume Loss in Ergodic Heat-Conducting Oscillators

Gibbs’ thermodynamic entropy is given by the logarithm of the phase volume, which itself responds to heat transfer to and from thermal reservoirs. We compare the thermodynamic dissipation described by (i) phase-volume loss with (ii) heat-transfer entropy production. Their equivalence is documented for computer simulations of the response of an ergodic harmonic oscillator to thermostated tempera...

Ergodic time-reversible chaos for Gibbs’ canonical oscillator

Quasiperiodicity and Chaos Chaos and Quasiperiodicity

Title of dissertation: QUASIPERIODICITY AND CHAOS Suddhasattwa Das, Doctor of Philosophy, 2015 Dissertation directed by: Professor James A. Yorke Department of Mathematics In this work, we investigate a property called “multi-chaos” is which a chaotic set has densely many hyperbolic periodic points of unstable dimension k embedded in it, for at least 2 different values of k. We construct a fami...

Undamped Harmonic Oscillator Driven by Additive Gaussian White Noise: a Statistical Analysis

While consistency of the maximum likelihood estimator of the drift matrix in a multi-dimensional continuous time Ornstein-Uhlenbeck process holds under rather general conditions, little is known about the rate of convergence and the limiting distribution of the estimator when the underlying process is not ergodic. The objective of the paper is to investigate these questions for an important exa...

Generalized dynamical thermostating technique.

We demonstrate that the Nosé method for constant-temperature molecular-dynamics simulation [Mol. Phys. 52, 255 (1984)] can be substantially generalized by the addition of auxiliary variables to encompass an infinite variety of Hamiltonian thermostats. Such thermostats can be used to enhance ergodicity in systems, such as the one-dimensional harmonic oscillator or certain molecular systems, for ...