Dynamical criticality in open systems: nonperturbative physics, microscopic origin, and direct observation

Abstract

Driven diffusive systems may undergo phase transitions to sustain atypical values of the current. This leads in some cases to symmetry-broken space-time trajectories which enhance the probability of such fluctuations. Here, we shed light on both the macroscopic large deviation properties and the microscopic origin of such spontaneous symmetry breaking in the open weakly asymmetric exclusion process. By studying the joint fluctuations of the current and a collective order parameter, we uncover the full dynamical phase diagram for arbitrary boundary driving, which is reminiscent of a Z2 symmetry-breaking transition. The associated joint large deviation function becomes nonconvex below the critical point, where a Maxwell-like violation of the additivity principle is observed. At the microscopic level, the dynamical phase transition is linked to an emerging degeneracy of the ground state of the microscopic generator, from which the optimal trajectories in the symmetry-broken phase follow. In addition, we observe this symmetry-breaking phenomenon in extensive rare-event simulations, confirming our macroscopic and microscopic results.

Citation

Pérez-Espigares, C., Carollo, F., Garrahan, J. P., & Hurtado, P. I. (2018). Dynamical criticality in open systems: nonperturbative physics, microscopic origin, and direct observation. Physical Review E, 98(6), Article 060102(R). https://doi.org/10.1103/physreve.98.060102

• Journal Article Type: Article
• Acceptance Date: Nov 21, 2018
• Online Publication Date: Dec 10, 2018
• Publication Date: Dec 10, 2018
• Deposit Date: Jan 3, 2019
• Publicly Available Date: Jan 3, 2019
• Journal: Physical Review E
• Print ISSN: 2470-0045
• Electronic ISSN: 2470-0053
• Publisher: American Physical Society
• Peer Reviewed: Peer Reviewed
• Volume: 98
• Issue: 6
• Article Number: 060102(R)
• DOI: https://doi.org/10.1103/physreve.98.060102
• Public URL: https://nottingham-repository.worktribe.com/output/1441666
• Publisher URL: https://journals.aps.org/pre/abstract/10.1103/PhysRevE.98.060102