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arXiv · 1909.02654

Analogy between equilibrium beach profiles and closed universes

Valerio Faraoni
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Abstract

We reformulate the variational problem describing equilibrium beach profiles in the thermodynamic approach of Jenkins and Inman. A first integral of the resulting Euler-Lagrange equation coincides formally with the Friedmann equation ruling closed universes in relativistic cosmology, leading to a useful analogy. Using the machinery of Friedmann-Lema\^{\i}tre-Robertson-Walker cosmology, qualitative properties and analytic solutions of beach profiles, which are the subject of a controversy, are elucidated.

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Valerio Faraoni. 2019-09-05. Analogy between equilibrium beach profiles and closed universes. https://doi.org/10.1103/physrevresearch.1.033002

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