Thermalization from quantum entanglement: jet simulations in the massive Schwinger model

TL;DR

This paper studies how quantum entanglement leads to thermalization in a quantum field theory model resembling jet production in QCD, demonstrating the emergence of thermodynamic behavior from unitary dynamics.

Contribution

It provides a detailed analysis of thermalization mechanisms driven by quantum entanglement in a field-theoretic setting, using the massive Schwinger model with external sources.

Findings

System approaches thermal equilibrium at late times.

Quantum entanglement drives the thermalization process.

Energy-momentum tensor dynamics align with hydrodynamic predictions.

Abstract

We investigate the emergence of thermalization in a quantum field-theoretic model mimicking the production of jets in QCD -- the massive Schwinger model coupled to external sources. Specifically, we compute the expectation values of local operators as functions of time and compare them to their thermal counterparts, quantify the overlap between the evolving density matrix and the thermal one, and compare the dynamics of the energy-momentum tensor to predictions from relativistic hydrodynamics. Through these studies, we find that the system approaches thermalization at late times and elucidate the mechanisms by which quantum entanglement drives thermalization in closed field-theoretic systems. Our results show how thermodynamic behavior emerges in real time from unitary quantum dynamics.