Biological & Soft Matter Seminar: Run and tumble dynamics in 1D

Abstract:

Run and tumble dynamics is a model that typically describes the motion of self-propelled particles, especially in the context of bacterial motility. It’s most famously used to model the behavior of E. coli and similar microorganisms. In the simplest setting, a run-and-tumble particle (RTP) moves with a fixed speed, undergoing random tumbling events at a constant rate. In one-dimension (1D), the overdamped dynamics of an RTP is described by a set of two Fokker-Planck equations, and the steady-state distribution is known for any arbitrary confining potential. In the talk, I will present three recent works presenting different extensions of the RTP model that consider: (i) inertial effects [1], (ii) tumbling at a non-constant rate (non-Markovian dynamics) [2], and (iii) run-and-tumble dynamics at a finite temperature (in contact with a heat bath) [3].

[1] N. R. Smith and OF, Phys. Rev. E 106, 054118 (2022).

[2] OF and N. R. Smith, Phys. Rev. E 109, 044121 (2024).

[3] RK Singh and OF, Submitted to Phys. Rev. E (2025)