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arXiv · 1105.1284

Shock waves in capillary collapse of colloids: a model system for two--dimensional screened Newtonian gravity

J. Bleibel·S. Dietrich·A. Dominguez·M. Oettel
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Abstract

Using Brownian dynamics simulations, density functional theory, and analytical perturbation theory we study the collapse of a patch of interfacially trapped, micrometer-sized colloidal particles, driven by long-ranged capillary attraction. This attraction {is formally analogous} to two--dimensional (2D) screened Newtonian gravity with the capillary length \hatλ as the screening length. Whereas the limit \hatλ \to \infty corresponds to the global collapse of a self--gravitating fluid, for finite \hatλ we predict theoretically and observe in simulations a ringlike density peak at the outer rim of a disclike patch, moving as an inbound shock wave. Possible experimental realizations are discussed.

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J. Bleibel, S. Dietrich, A. Dominguez, M. Oettel. 2011-09-02. Shock waves in capillary collapse of colloids: a model system for two--dimensional screened Newtonian gravity. https://doi.org/10.1103/physrevlett.107.128302

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