A Field-Theoretic Model for Chemotaxis in Run and Tumble Particles

TL;DR

This paper introduces a field-theoretic model for run and tumble chemotaxis that captures collective behaviors like aggregation and self-chemotaxis in particles, bridging microscopic interactions and macroscopic phases.

Contribution

It develops a novel continuum framework based on density functional theory to describe collective chemotactic behaviors with particle resolution on diffusive timescales.

Findings

Model exhibits particle aggregation in external attractant fields.

Captures self-chemotaxis-driven aggregation.

Framework applicable to continuum phases with multi-particle interactions.

Abstract

In this paper we develop a field-theoretic description for run and tumble chemotaxis, based on a density functional description of crystalline materials modified to capture orientational ordering. We show that this framework, with its in-built multi-particle interactions, soft-core repulsion and elasticity is ideal for describing continuum collective phases with particle resolution, but on diffusive timescales. We show that our model exhibits particle aggregation in an externally imposed constant attractant field, as is observed for phototactic or thermotactic agents. We also show that this model captures particle aggregation through self-chemotaxis, an important mechanism that aids quorum dependent cellular interactions.