BRANCHING PARTICLE-SYSTEMS AND SUPERPROCESSES
成果类型:
Article
署名作者:
DYNKIN, EB
刊物名称:
ANNALS OF PROBABILITY
ISSN/ISSBN:
0091-1798
DOI:
10.1214/aop/1176990339
发表日期:
1991
页码:
1157-1194
关键词:
super-brownian motion
additive-functionals
CONSTRUCTION
摘要:
We start from a model of a branching particle system with immigration and with death rate and branching mechanism depending on time and location. Then we consider a limit case when the mass of particles and their life times are small and their density is high. This way, we construct a measure-valued process X(t) which we call a superprocess. Replacing the underlying Markov process xi-t by the corresponding historical process xi less-than-or-equal-to t, we construct a measure-valued process M(t) in functional spaces which we call a historical superprocess. The moment functions for superprocesses are evaluated. Linear positive additive functionals are studied. They are used to construct a continuous analog of a random tree obtained by stopping every particle at a time depending on its path (say, at the first exit time from a domain). A related special Markov property for superprocesses is proved which is useful for applications to certain nonlinear partial differential equations. The concluding section is devoted to a survey of the literature, and the terminology on Markov processes used in the paper is explained in the Appendix.