QUANTUM DISSIPATION AND QUANTUM NOISE

TL;DR

This paper derives the exact quantum action for damped systems using path integrals, linking phase-space doubling to quantum noise, and advances understanding of quantum dissipation.

Contribution

It provides a novel derivation of the quantum dissipative action from path integral methods, clarifying the role of phase-space doubling and quantum noise effects.

Findings

Exact quantum action for damped systems derived

Phase-space doubling relates to quantum noise

Enhanced understanding of quantum dissipation mechanisms

Abstract

We derive the exact action for a damped mechanical system ( and the special case of the linear oscillator) from the path integral formulation of the quantum Brownian motion problem developed by Schwinger and by Feynman and Vernon. The doubling of the phase-space degrees of freedom for dissipative systems and thermal field theories is discussed and the initial values of the doubled variables are related to quantum noise effects.