Dynamics of a run and tumble particle in contact with a heat bath

by Dr RK Singh (Bar-Ilan University, Israel)

Thursday 28 Nov 2024, 11:00 → 12:00 Asia/Kolkata

A (304 (DTP Seminar Rooom))

We study the dynamics of a run and tumble particle (RTP) in a confining potential in contact with a heat bath. When coupled to a heat bath, the dynamics of an RTP is equivalent to that of a Brownian particle moving in a fluctuating potential. We study confining potentials of the form
$U(x) ∼ |x|^a$ and show that the steady state of the RTP has an infinite support for every $a > 0$. We analyze the special case of anharmonic confinement with $a = 1$, and study the steady state, relaxation, and first passage properties. We find that unlike an RTP at zero temperature or a Brownian motion in a $|x|$ potential, the RTP in contact with the heat bath exhibits a mixture of Gaussian distributions at small times and approaches a mixture of Laplace distributions as the steady state. When an absorbing wall is placed at the origin, then the average time taken by the RTP to reach the wall starting at a location away from the wall is always greater than the average time taken by the corresponding Brownian particle.