Hamiltonians representing equations of motion with damping due to friction

Suppose that $H(q,p)$ is a Hamiltonian on a manifold M, and $\tilde L(q,\dot q)$, the Rayleigh dissipation function, satisfies the same hypotheses as a Lagrangian on the manifold M. We provide a Hamiltonian framework that gives the equation $$ \dot q = \frac{\partial H}{\partial p}(q,p) ,...

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Bibliographic Details
Main Author: Stephen Montgomery-Smith
Format: Article
Language:English
Published: Texas State University 2014-04-01
Series:Electronic Journal of Differential Equations
Subjects:
Online Access:http://ejde.math.txstate.edu/Volumes/2014/89/abstr.html
Description
Summary:Suppose that $H(q,p)$ is a Hamiltonian on a manifold M, and $\tilde L(q,\dot q)$, the Rayleigh dissipation function, satisfies the same hypotheses as a Lagrangian on the manifold M. We provide a Hamiltonian framework that gives the equation $$ \dot q = \frac{\partial H}{\partial p}(q,p) , \quad \dot p = - \frac{\partial H}{\partial q}(q,p) - \frac{\partial \tilde L}{\partial \dot q}(q,\dot q) $$ The method is to embed M into a larger framework where the motion drives a wave equation on the negative half line, where the energy in the wave represents heat being carried away from the motion. We obtain a version of Nother's Theorem that is valid for dissipative systems. We also show that this framework fits the widely held view of how Hamiltonian dynamics can lead to the ``arrow of time.''
ISSN:1072-6691