Universality, Robustness, and Limits of the Eigenstate Thermalization Hypothesis in Open Quantum Systems
Abstract
The eigenstate thermalization hypothesis (ETH) underpins much of our modern understanding of the thermalization of closed quantum many-body systems. Here, we investigate the statistical properties of observables in the eigenbasis of the Lindbladian operator of a Markovian open quantum system. We demonstrate the validity of a Lindbladian ETH ansatz through extensive numerical simulations of several physical models. To highlight the robustness of Lindbladian ETH, we consider what we dub the dilute-click regime of the model, in which one postselects only quantum trajectories with a finite fraction of quantum jumps. The average dynamics are generated by a non-trace-preserving Liouvillian, and we show that the Lindbladian ETH ansatz still holds in this case. On the other hand, the no-click limit is a singular point at which the Lindbladian reduces to a doubled non-Hermitian Hamiltonian and Lindbladian ETH breaks down.
Cite
@article{arxiv.2504.10261,
title = {Universality, Robustness, and Limits of the Eigenstate Thermalization Hypothesis in Open Quantum Systems},
author = {Gabriel Almeida and Pedro Ribeiro and Masudul Haque and Lucas Sá},
journal= {arXiv preprint arXiv:2504.10261},
year = {2026}
}
Comments
7 pages, 5 figures Published in Phys. Rev. E