Electronic Journal of Probability
- Electron. J. Probab.
- Volume 19 (2014), paper no. 53, 46 pp.
Subcritical contact processes seen from a typical infected site
What is the long-time behavior of the law of a contact process started with a single infected site, distributed according to counting measure on the lattice? This question is related to the configuration as seen from a typical infected site and gives rise to the definition of so-called eigenmeasures, which are possibly infinite measures on the set of nonempty configurations that are preserved under the dynamics up to a time-dependent exponential factor. In this paper, we study eigenmeasures of contact processes on general countable groups in the subcritical regime. We prove that in this regime, the process has a unique spatially homogeneous eigenmeasure. As an application, we show that the law of the process as seen from a typical infected site, chosen according to a Campbell law, converges to a long-time limit. We also show that the exponential decay rate of the expected number of infected sites is continuously differentiable and strictly increasing as a function of the recovery rate, and we give a formula for the derivative in terms of the long time limit law of the process as seen from a typical infected site.
Electron. J. Probab., Volume 19 (2014), paper no. 53, 46 pp.
Accepted: 23 June 2014
First available in Project Euclid: 4 June 2016
Permanent link to this document
Digital Object Identifier
Mathematical Reviews number (MathSciNet)
Zentralblatt MATH identifier
Primary: 82C22: Interacting particle systems [See also 60K35]
Secondary: 60K35: Interacting random processes; statistical mechanics type models; percolation theory [See also 82B43, 82C43] 82B43: Percolation [See also 60K35]
This work is licensed under a Creative Commons Attribution 3.0 License.
Sturm, Anja; Swart, Jan. Subcritical contact processes seen from a typical infected site. Electron. J. Probab. 19 (2014), paper no. 53, 46 pp. doi:10.1214/EJP.v19-2904. https://projecteuclid.org/euclid.ejp/1465065695