Effective run-and-tumble dynamics of bacteria baths

Abstract

{\it E. coli} bacteria swim in straight runs interrupted by sudden reorientation events called tumbles. The resulting random walks give rise to density fluctuations that can be derived analytically in the limit of non interacting particles or equivalently of very low concentrations. However, in situations of practical interest, the concentration of bacteria is always large enough to make interactions an important factor. Using molecular dynamics simulations, we study the dynamic structure factor of a model bacterial bath for increasing values of densities. We show that it is possible to reproduce the dynamics of density fluctuations in the system using a free run-and-tumble model with effective fitting parameters. We discuss the dependence of these parameters, e.g., the tumbling rate, tumbling time and self-propulsion velocity, on the density of the bath.

References in corpus (14)

• Novel type of phase transition in a system of self-driven particles
• Flocks, herds, and schools: A quantitative theory of flocking
• Statistical Mechanics of Interacting Run-and-Tumble Bacteria
• Collective motion of self-propelled particles interacting without cohesion
• Diffusive transport without detailed balance in motile bacteria: Does microbiology need statistical physics?
• Boltzmann and hydrodynamic description for self-propelled particles
• Differential Dynamic Microscopy: Probing wave vector dependent dynamics with a microscope
• Hydrodynamic equations for self-propelled particles: microscopic derivation and stability analysis
• Pattern formation in self-propelled particles with density-dependent motility
• Self-Starting Micromotors in a Bacterial Bath
• Enhanced diffusion and ordering of self-propelled rods
• Differential Dynamic Microscopy of Bacterial Motility
• Differential Dynamic Microscopy: a High-Throughput Method for Characterizing the Motility of Microorganism
• Hydrodynamics of bacterial motion

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• Exact stationary state of a run-and-tumble particle with three internal states in a harmonic trap
• Can the self-propulsion of anisotropic microswimmers be described by using forces and torques?
• Self-Sustained Density Oscillations of Swimming Bacteria Confined in Microchambers
• Predictive local field theory for interacting active Brownian spheres in two spatial dimensions
• Collective dynamics of active Brownian particles in three spatial dimensions: a predictive field theory
• Narrow-escape time and sorting of active particles in circular domains
• Run-and-tumble particles in speckle fields
• First passage statistics of active random walks on one and two dimensional lattices