Approach to Microcanonical Equilibrium for Nonisolated Systems

TL;DR

This paper investigates how nonisolated systems reach microcanonical equilibrium through interactions with low-energy pulses, treating interactions exactly without perturbation, and discusses the origins of time asymmetry and recurrence absence.

Contribution

It introduces a method to analyze equilibrium in nonisolated systems with weak, random interactions without relying on perturbation theory.

Findings

Microcanonical equilibrium is achieved under specified conditions.

Interactions can be treated exactly despite being weak.

Time asymmetry and recurrence absence are explained.

Abstract

The approach to equilibrium for systems interacting with their environment by being regularly exposed to low energy, low intensity pulses of some type of quanta is studied. Assuming a randomness condition on the interaction of these quanta with the system, but making no assumptions about the accessible states of the system, we show that microcanonical equilibrium is reached. Although the intensity of the pulses is assumed to be weak the interactions are treated exactly, with no recourse to perturbation theory. The origin of time asymmetry and the absence of recurrence is discussed.