Clustering of quorum sensing colloidal particles

We propose a simple model of colloidal suspension, whereby individual particles change their diffusivity from high (hot) to low (cold), as the local concentration of their closest peers grows larger than a certain threshold. Such a non-reciprocal interactive mechanism is known in biology as quorum sensing. Upon tuning the parameters of the adopted quorum sensing protocol, the suspension is numerically shown to go through a variety of two-phase (hot and cold) configurations. This is an archetypal model with potential applications in robotics and social studies.