1 research outputs found
Lattice Models of Nonequilibrium Bacterial Dynamics
We study a model of self propelled particles exhibiting run and tumble
dynamics on lattice. This non-Brownian diffusion is characterised by a random
walk with a finite persistence length between changes of direction, and is
inspired by the motion of bacteria such as E. coli. By defining a class of
models with multiple species of particle and transmutation between species we
can recreate such dynamics. These models admit exact analytical results whilst
also forming a counterpart to previous continuum models of run and tumble
dynamics. We solve the externally driven non-interacting and zero-range
versions of the model exactly and utilise a field theoretic approach to derive
the continuum fluctuating hydrodynamics for more general interactions. We make
contact with prior approaches to run and tumble dynamics off lattice and
determine the steady state and linear stability for a class of crowding
interactions, where the jump rate decreases as density increases. In addition
to its interest from the perspective of nonequilibrium statistical mechanics,
this lattice model constitutes and efficient tool to simulate a class of
interacting run and tumble models relevant to bacterial motion, so long as
certain conditions (that we derive) are met.Comment: 33 pages, 12 figure