2020/02/27 by Yichen Fu, Hong Qin, Fu, Yichen +1
Physics and Astronomy · #FOS: Physical sciences #Fluid Dynamics (physics.flu-dyn) #Plasma Physics (physics.plasm-ph) #Quantum Mechanics and Non-Hermitian Physics #Quantum chaos and dynamical systems #Quantum, superfluid, helium dynamics
paper · pdf · doi:10.48550/arxiv.2002.12279
openalex publication_date 2020/02/27 · openalex created_date 2020/03/06 · openalex updated_date 2026/07/28
We show that the dynamics, in particular the Kelvin-Helmholtz (KH) instability, of an inviscid fluid with velocity shear admits Parity-Time (PT) symmetry, which provides a physical explanation to the well-known observation that the spectrum of the perturbation eigenmodes of the system is symmetric with respect to the real axis. It is found that the KH instability is triggered when and only when the PT symmetry is spontaneously broken. The analysis of PT symmetry also reveals that the relative phase between parallel velocity and pressure perturbations needs to be locked at π/2 when the instability is suppressed.