Friction in a Model of Hamiltonian Dynamics

TL;DR

This paper models the motion of a heavy particle in a Bose-Einstein condensate, revealing how Cerenkov radiation causes friction and deceleration through a Hamiltonian dynamics framework.

Contribution

It introduces a Hamiltonian model capturing friction via Cerenkov radiation emission in a Bose gas, a novel approach in this context.

Findings

Friction arises from Cerenkov radiation emission.

The particle decelerates and comes to rest due to this friction.

The dynamics are described by nonlinear Hamiltonian equations.

Abstract

We study the motion of a heavy tracer particle weakly coupled to a dense ideal Bose gas exhibiting Bose-Einstein condensation. In the so-called mean-field limit, the dynamics of this system approaches one determined by nonlinear Hamiltonian evolution equations describing a process of emission of Cerenkov radiation of sound waves into the Bose-Einstein condensate along the particle's trajectory. The emission of Cerenkov radiation results in a friction force with memory acting on the tracer particle and causing it to decelerate until it comes to rest.