Large deviations at various levels for run-and-tumble processes with space-dependent velocities and space-dependent switching rates
Cécile Monthus
Abstract
Abstract One-dimensional run-and-tumble processes may converge towards some localized non-equilibrium steady states when the two velocities and/or the two switching rates are space-dependent. A long dynamical trajectory can be then analyzed via the large deviations at level 2.5 for the joint probability of the empirical densities, of the empirical spatial currents and of the empirical switching flows. Level 2 for the empirical densities alone can be then derived via the optimization of level 2.5 over the empirical flows. More generally, the large deviations of any time-additive observable can be also obtained via contraction from level 2.5, or equivalently via the deformed generator method and the corresponding Doob conditioned process. Finally, the large deviations for the empirical intervals between consecutive switching events can be obtained via the introduction of the alternate Markov chain that governs the series of all of the switching events of a long trajectory.