# Diffusion and entanglement in open quantum systems

## TL;DR

This paper introduces a microscopic model of open quantum systems that demonstrates genuine quantum diffusion and entanglement at hydrodynamic scales, bridging classical and quantum non-equilibrium theories.

## Contribution

It constructs a quantum open system exhibiting diffusive behavior and entanglement, advancing the understanding of quantum hydrodynamics.

## Key findings

- The system shows diffusive scaling in quantum dynamics.
- Hydrodynamic entanglement persists at macroscopic scales.
- Provides a foundation for quantum non-equilibrium hydrodynamics.

## Abstract

The macroscopic fluctuation theory provides a complete hydrodynamic description of non-equilibrium classical diffusive systems. As a first step towards a diffusive theory of open quantum systems, we show how to construct a microscopic open quantum system that exhibits genuine quantum diffusive scaling. Namely, the dynamics is diffusive and the density matrix is entangled in the hydrodynamic length and time scales.