Mutually catalytic branching in the plane: Finite measure states

• 成果类型: Article
• 署名作者: Dawson, DA; Etheridge, AM; Fleischmann, K; Mytnik, L; Perkins, EA; Xiong, J
• 署名单位: Carleton University; University of Oxford; Leibniz Association; Weierstrass Institute for Applied Analysis & Stochastics; Technion Israel Institute of Technology; University of British Columbia; University of Tennessee System; University of Tennessee Knoxville
• 刊物名称: ANNALS OF PROBABILITY
• ISSN/ISSBN: 0091-1798
• 发表日期: 2002
• 页码: 1681-1762
• 关键词: partial-differential equations; super-brownian motion; uniqueness; DIFFUSIONS; BEHAVIOR

摘要

We study a pair of populations in R-2 which undergo diffusion and branching. The system is interactive in that the branching rate of each type is proportional to the local density of the other type. For a diffusion rate sufficiently large compared with the branching rate, the model is constructed as the unique pair of finite measure-valued processes which satisfy a martingale problem involving the collision local time of the solutions. The processes are shown to have densities at fixed times which live on disjoint sets and explode as they approach the interface of the two populations. In the long-term limit, global extinction of one type is shown. The process constructed is a rescaled limit of the corresponding Z(2)-lattice model studied by D. A. Dawson and E. A. Perkins [Ann. Probab. 26 (1998) 1088-1138] and resolves the large scale mass-time-space behavior of that model.