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arXiv · 2112.09511

How do CPT-like symmetries shape the stability of geophysical flows?

Tomos W. David·Pierre Delplace·Antoine Venaille
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Abstract

We examine the role discrete symmetries, time-reversal and mirror symmetries, play in the context of geophysical waves and instabilities. By looking at three special cases from the two-layer quasi-geostrophic model as well as developing a general framework for translating real-space transformations to Fourier-space we are able to: 1) show that baroclinic instability is an example of spontaneous parity-time symmetry breaking; 2) show that pure parity symmetry for a fluid system is exactly analogous to charge-conjugation-parity symmetry in a condensed matter system; and 3) show that when a pure parity symmetry is broken, this is associated with the suppression of wave propagation. Further, in the latter case, instability can arise without a corresponding symmetry breaking. This study highlights the role of symmetry breaking behind the dynamics of geophysical waves and instabilities.

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Tomos W. David, Pierre Delplace, Antoine Venaille. 2021-12-17. How do CPT-like symmetries shape the stability of geophysical flows?. https://doi.org/10.1063/5.0088936

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