Suppression of hyperuniformity in hydrodynamic scalar active field theories

TL;DR

This paper investigates how hydrodynamic interactions affect hyperuniformity in active scalar field theories, showing that activity can suppress hyperuniform patterns in wet active systems described by active model H.

Contribution

It demonstrates that hydrodynamic interactions and activity interplay to suppress hyperuniformity in wet active scalar field theories, extending understanding beyond passive models.

Findings

Passive model H exhibits hyperuniformity during coarsening.

Active model H with contractile stress suppresses hyperuniformity.

Hydrodynamic interactions influence pattern formation in active systems.

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.