Scientific Calendar Event

Starts 21 Mar 2023 11:00
Ends 21 Mar 2023 12:00
Central European Time
Hybrid Seminar
room 128 (SISSA, via Bonomea) + Zoom
Gabriele Perfetto

In the talk I will present a new theory to access large scale correlations and fluctuations in generic non-stationary and inhomogeneous situations, where hydrodynamic motion takes place. This theory is inspired by the well-known macroscopic fluctuation theory (MFT). The latter is the hydrodynamic large-deviation theory, which has been successfully applied to a variety of classical systems, for fluctuations beyond mean values of purely diffusive fluxes. The ``ballistic macroscopic fluctuation theory’’ (BMFT) focuses, instead, on the Euler scale, which exists and is non trivial for systems, classical or quantum, admitting ballistic transport. The BMFT requires as input solely the Euler hydrodynamic data of the system. It is a large-deviation theory formulated on the basis of an action principle over hydrodynamic space-time trajectories from which fluid correlations and current fluctuations can be derived. Strikingly, the theory predicts the novel effect that initially uncorrelated fluid regions develop over time long-range correlations, which invalidate, for correlations, the local relaxation assumption at the basis of the description of hydrodynamics’mean values.

In the talk I will discuss the principles underlying the BMFT, its formulation and how the aforementioned results are obtained.
Based on:
B.Doyon, G. Perfetto, T. Sasamoto, T. Yoshimura: arxiv: 2206.14167 (2022)
B.Doyon, G. Perfetto, T. Sasamoto, T. Yoshimura: arXiv: 2210.10009 (2022)