## Electronic Journal of Probability

### Perturbations of Voter model in one-dimension

#### Abstract

We study the scaling limit of a large class of voter model perturbations in one dimension, including stochastic Potts models, to a universal limiting object, the continuum voter model perturbation. The perturbations can be described in terms of bulk and boundary nucleations of new colors (opinions). The discrete and continuum (space) models are obtained from their respective duals, the discrete net with killing and Brownian net with killing. These determine the color genealogy by means of reduced graphs. We focus our attention on models where the voter and boundary nucleation dynamics depend only on the colors of nearest neighbor sites, for which convergence of the discrete net with killing to its continuum analog was proved in an earlier paper by the authors. We use some detailed properties of the Brownian net with killing to prove voter model perturbations converge to their continuum counterparts. A crucial property of reduced graphs is that even in the continuum, they are finite almost surely. An important issue is how vertices of the continuum reduced graphs are strongly approximated by their discrete analogues.

#### Article information

Source
Electron. J. Probab., Volume 22 (2017), paper no. 34, 42 pp.

Dates
Accepted: 5 February 2017
First available in Project Euclid: 18 April 2017

https://projecteuclid.org/euclid.ejp/1492502428

Digital Object Identifier
doi:10.1214/17-EJP37

Mathematical Reviews number (MathSciNet)
MR3646060

Zentralblatt MATH identifier
1362.60088

#### Citation

Newman, C.M.; Ravishankar, K.; Schertzer, E. Perturbations of Voter model in one-dimension. Electron. J. Probab. 22 (2017), paper no. 34, 42 pp. doi:10.1214/17-EJP37. https://projecteuclid.org/euclid.ejp/1492502428

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