## The Annals of Applied Probability

### Equilibrium interfaces of biased voter models

#### Abstract

A one-dimensional interacting particle system is said to exhibit interface tightness if starting in an initial condition describing the interface between two constant configurations of different types, the process modulo translations is positive recurrent. In a biological setting, this describes two populations that do not mix, and it is believed to be a common phenomenon in one-dimensional particle systems. Interface tightness has been proved for voter models satisfying a finite second moment condition on the rates. We extend this to biased voter models. Furthermore, we show that the distribution of the equilibrium interface for the biased voter model converges to that of the voter model when the bias parameter tends to zero. A key ingredient is an identity for the expected number of boundaries in the equilibrium voter model interface, which is of independent interest.

#### Article information

Source
Ann. Appl. Probab., Volume 29, Number 4 (2019), 2556-2593.

Dates
Revised: October 2018
First available in Project Euclid: 23 July 2019

https://projecteuclid.org/euclid.aoap/1563869050

Digital Object Identifier
doi:10.1214/19-AAP1461

Mathematical Reviews number (MathSciNet)
MR3984257

#### Citation

Sun, Rongfeng; Swart, Jan M.; Yu, Jinjiong. Equilibrium interfaces of biased voter models. Ann. Appl. Probab. 29 (2019), no. 4, 2556--2593. doi:10.1214/19-AAP1461. https://projecteuclid.org/euclid.aoap/1563869050

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