Decoherence, Re-coherence, and the Black Hole Information Paradox

TL;DR

This paper studies how a quantum oscillator coupled to a field experiences rapid decoherence but eventually re-coheres into a pure state, offering insights into quantum theory interpretation and black hole information loss.

Contribution

It presents a model demonstrating re-coherence in open quantum systems and explores its implications for black hole information paradox.

Findings

Oscillator loses coherence quickly due to environment

System re-coheres into a pure ground state over time

Implications for quantum interpretation and black hole information

Abstract

We analyze a system consisting of an oscillator coupled to a field. With the field traced out as an environment, the oscillator loses coherence on a very short {\it decoherence timescale}; but, on a much longer {\it relaxation timescale}, predictably evolves into a unique, pure (ground) state. This example of {\it re-coherence} has interesting implications both for the interpretation of quantum theory and for the loss of information during black hole evaporation. We examine these implications by investigating the intermediate and final states of the quantum field, treated as an open system coupled to an unobserved oscillator.