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arXiv · 1810.02640

Stable Configurations Of Charged Sedimenting Particles

C. I. Trombley·M. L. Ekiel-Jezewska
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Abstract

The qualitative behavior of charged particles in a vacuum is given by Earnshaw's Theorem which states that there is no steady configuration of charged particles in a vacuum which is asymptotically stable to perturbations. In a viscous fluid, examples of stationary configurations of sedimenting uncharged particles are known, but they are unstable or neutrally stable - they are not attractors. In this paper, it is shown by example that two charged particles settling in a fluid may have a configuration which is asymptotically stable to perturbations, for a wide range of charges, radii and densities. The existence of such "bound states" is essential from a fundamental point of view and it can be significant for dilute charged particulate systems in various biological, medical and industrial contexts.

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C. I. Trombley, M. L. Ekiel-Jezewska. 2018-10-08. Stable Configurations Of Charged Sedimenting Particles. https://doi.org/10.1103/physrevlett.121.254502

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