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Star-triangle equivalence in soap froths

M. Mancini·Ch. Oguey
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Abstract

In two dimensional foams at equilibrium, triangular bubbles can be freely exchanged with 3-fold stars --three edges ending at a central vertex. This theorem is deduced here from Moukarzel's duality. Moreover, to probe the method, a few related properties are established: under slow gas diffusion, T2 processes are continuous for triangles but not for other types of bubbles. In general, the gas flow results in different configurations in the presence of a triangle than in the presence of a star.

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M. Mancini, Ch. Oguey. 2003-03-24. Star-triangle equivalence in soap froths. https://doi.org/10.1080/09500830310001594291

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