2019/01/31 by Tibor Rakovszky, Frank Pollmann, Curt von Keyserlingk +1 · 2 citations
Mathematics · Physics and Astronomy · #Diffusion #Entropy (arrow of time) #Mathematics #Model Reduction and Neural Networks #Opinion Dynamics and Social Influence #Physics #Pure mathematics #Quantum #Quantum entanglement #Quantum many-body systems #Quantum mechanics #Statistical physics #Von Neumann architecture #Von Neumann entropy #cond-mat.stat-mech #cond-mat.str-el
paper · pdf · doi:10.1103/physrevlett.122.250602
published as Phys. Rev. Lett. 122, 250602 (2019) · close to published version: 4 + epsilon pages, 3 figures + supplement
openalex publication_date 2019/06/25 · arxiv created 2019/07/26 · arxiv updated 2019/07/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
We investigate the dynamics of quantum entanglement after a global quench and uncover a qualitative difference between the behavior of the von Neumann entropy and higher Rényi entropies. We argue that the latter generically grow sub-ballistically, as ∝sqrt[t], in systems with diffusive transport. We provide strong evidence for this in both a U(1) symmetric random circuit model and in a paradigmatic nonintegrable spin chain, where energy is the sole conserved quantity. We interpret our results as a consequence of local quantum fluctuations in conserved densities, whose behavior is controlled by diffusion, and use the random circuit model to derive an effective description. We also discuss the late-time behavior of the second Rényi entropy and show that it exhibits hydrodynamic tails with three distinct power laws occurring for different classes of initial states.