Suppression of hyperuniformity in hydrodynamic scalar active field theories

Nadia Bihari Padhan; Axel Voigt

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arXiv · 2411.17409

Suppression of hyperuniformity in hydrodynamic scalar active field theories

Nadia Bihari Padhan·Axel Voigt

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Abstract

The coarsening dynamics at late times in phase-separating systems lead to universally hyperuniform patterns. This is well known for scalar field theories, such as the Cahn-Hilliard equation, but has also been shown for dry scalar active field theories. We demonstrate the role of hydrodynamic interactions in influencing hyperuniformity in a wet active system described by active model H. Our direct numerical simulations reveal that, while (passive) model H shows hyperuniformity in the coarsening regime, the interplay of activity and hydrodynamic interactions suppresses hyperuniformity in active model H, especially when the activity generates contractile stress in the fluid.

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Nadia Bihari Padhan, Axel Voigt. 2024-11-26. Suppression of hyperuniformity in hydrodynamic scalar active field theories. https://arxiv.org/abs/2411.17409

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