Microscopic derivation of curvature-driven interfacial propulsion

Derive the curvature-driven advective flux mechanism of Active Model H− from a microscopic model of self-propelled particles near fluid interfaces.

Background

Active Model H− is a scalar phase-field theory in which a curvature-motivated interfacial stress generates an advective flux. The proposed mechanism explains how the model maintains uniformly thick filament connections and produces curvature-driven propulsion toward the convex side of an interface.

The paper notes that the proposed explanation is based on the observed composition profiles, but that the flux near network junctions has not been directly measured. A microscopic derivation from the behavior of self-propelled particles near interfaces would therefore clarify the physical origin and validity of the phenomenological mechanism.