Hydrodynamics of low-dimensional interacting systems: Advances, challenges, and future directions

Unified description of hydrodynamic and Nambu–Goldstone modes in open and closed systems

Jun 9, 2025, 11:30 AM

45m

Panasonic Auditorium, Yukawa Hall (Yukawa Institute for Theoretical Physics, Kyoto University)

Speaker

Yoshimasa Hidaka

Description

I present a unified effective theory of hydrodynamic and Nambu–Goldstone (NG) modes in both closed and open systems. A central focus is the distinction between strong and weak symmetries, which clarifies how NG modes can emerge even in the absence of conserved charges, as in open systems. Using the Schwinger–Keldysh formalism, I classify NG modes and derive their dispersion relations, including both type-A and type-B modes.