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arXiv · 1810.11460

Kelvin-Helmholtz instability is the result of parity-time symmetry breaking

Hong Qin·Ruili Zhang·Alexander S. Glasser·Jianyuan Xiao
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Abstract

Parity-Time (PT)-symmetry is being actively investigated as a fundamental property of observables in quantum physics. We show that the governing equations of the classical two-fluid interaction and the incompressible fluid system are PT-symmetric, and the well-known Kelvin-Helmholtz instability is the result of spontaneous PT-symmetry breaking. It is expected that all classical conservative systems governed by Newton's law admit PT-symmetry, and the spontaneous breaking thereof is a generic mechanism for classical instabilities. Discovering the PT-symmetry of systems in fluid dynamics and plasma physics and identifying the PT-symmetry breaking responsible for instabilities enable new techniques to classical physics and enrich the physics of PT-symmetry.

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Hong Qin, Ruili Zhang, Alexander S. Glasser, Jianyuan Xiao. 2018-10-28. Kelvin-Helmholtz instability is the result of parity-time symmetry breaking. https://doi.org/10.1063/1.5088498

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