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arXiv · 2502.09666

Coupled dynamics of chiral waves and gyroscopic systems with applications to atmospheric phenomena

Alessio Kandiah·Ian S. Jones·Natasha V. Movchan·Alexander B. Movchan
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Abstract

The present paper introduces the notion of chiral gravitational elastic waves and explores their connections to equatorial and planetary waves. The analysis of the gravity-induced waveforms in gyroscopic systems composed of gyropendulums provides important insights into the dynamics of waves in the vicinity of the equatorial belt. We show that the direction of motion of the chiral waveforms can be controlled by choosing the orientation of the spinners. The presence of gravity is shown to affect the stop band frequencies for such structures, providing an additional control parameter for the chiral waveguides. The effect of the Coriolis force is demonstrated for chiral continuum models describing waves in the equatorial region and the polar regions on a rotating sphere. Additional asymptotic features of equatorial waves are presented in this paper. We show that the shape of a ridge of a polar vortex can be approximated by the governing equations of a gyropendulum. The theoretical work is accompanied by illustrative examples.

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Alessio Kandiah, Ian S. Jones, Natasha V. Movchan, Alexander B. Movchan. 2025-02-12. Coupled dynamics of chiral waves and gyroscopic systems with applications to atmospheric phenomena. https://arxiv.org/abs/2502.09666

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