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Penta-hepta defect chaos in a model for rotating hexagonal convection

Yuan-Nan Young·Hermann Riecke
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Abstract

In a model for rotating non-Boussinesq convection with mean flow we identify a regime of spatio-temporal chaos that is based on a hexagonal planform and is sustained by the {\it induced nucleation} of dislocations by penta-hepta defects. The probability distribution function for the number of defects deviates substantially from the usually observed Poisson-type distribution. It implies strong correlations between the defects inthe form of density-dependent creation and annihilation rates of defects. We extract these rates from the distribution function and also directly from the defect dynamics.

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Yuan-Nan Young, Hermann Riecke. 2002-09-19. Penta-hepta defect chaos in a model for rotating hexagonal convection. https://doi.org/10.1103/physrevlett.90.134502

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