Exact formulas for two interacting particles and applications in particle systems with duality

Exact formulas for two interacting particles and applications in particle systems with duality

Carinci, G. (TU Delft Applied Probability)
Giardina', C. (Università Degli Studi di Modena e Reggio Emilia)
Redig, F.H.J. (TU Delft Applied Probability)

2020-08

We consider two particles performing continuous-time nearest neighbor random walk on Z and interacting with each other when they are at neighboring positions. The interaction is either repulsive (partial exclusion process) or attractive (inclusion process). We provide an exact formula for the Laplace-Fourier transform of the transition probabilities of the two-particle dynamics. From this we derive a general scaling limit result, which shows that the possible scaling limits are coalescing Brownian motions, reflected Brownian motions and sticky Brownian motions. In particle systems with duality, the solution of the dynamics of two dual particles provides relevant information. We apply the exact formula to the the symmetric inclusion process, that is self-dual, in the condensation regime. We thus obtain two results. First, by computing the time-dependent covariance of the particle occupation number at two lattice sites we characterise the time-dependent coarsening in infinite volume when the process is started from a homogeneous product measure. Second, we identify the limiting variance of the density field in the diffusive scaling limit, relating it to the local time of sticky Brownian motion.

Condensation
Duality
Inclusion process
Interacting particle systems

http://resolver.tudelft.nl/uuid:b938f7ee-a901-47f7-9064-65d54f6b2dbf

https://doi.org/10.1214/19-AAP1548

1050-5164

Annals of Applied Probability, 30 (4), 1934-1970

Institutional Repository

journal article

© 2020 G. Carinci, C. Giardina', F.H.J. Redig