Original article at: http://www.math.washington.edu/~ejpecp/viewarticle.php?id=1229

Collision Local Times, Historical Stochastic Calculus, and Competing Species

Steven N. Evans, University of California at Berkeley
Edwin A. Perkins, The University of British Columbia

Abstract

Branching measure-valued diffusion models are investigated that can be regarded as pairs of historical Brownian motions modified by a competitive interaction mechanism under which individuals from each population have their longevity or fertility adversely affected by collisions with individuals from the other population. For 3 or fewer spatial dimensions, such processes are constructed using a new fixed-point technique as the unique solution of a strong equation driven by another pair of more explicitly constructible measure-valued diffusions. This existence and uniqueness is used to establish well-posedness of the related martingale problem and hence the strong Markov property for solutions. Previous work of the authors has shown that in 4 or more dimensions models with the analogous definition do not exist.

Full text: PDF | PostScript




Copyright for articles published in this journal is retained by the authors, with first publication rights granted to the journal. By virtue of their appearance in this open access journal, articles are free to use, with proper attribution, in educational and other non-commercial settings. The authors of papers published in EJP/ECP retain the copyright. We ask for the permission to use the material in any form. We also require that the initial publication in EJP or ECP is acknowledged in any future publication of the same article. Before a paper is published in the Electronic Journal of Probability or Electronic Communications in Probability we must receive a hard-copy of the copyright form. Please mail it to Philippe Carmona Laboratoire Jean Leray UMR 6629 Universite de Nantes, 2, Rue de la Houssinière BP 92208 F-44322 Nantes Cédex 03 France You can also send it by FAX: (33|0) 2 51 12 59 12 to the attention of Philippe Carmona. You can even send a scanned jpeg or pdf of this copyright form to the managing editor ejpecpme@math.univ-nantes.fr. as an attached file. If a paper has several authors, the corresponding author signs the copyright form on behalf of all the authors.

Original article at: http://www.math.washington.edu/~ejpecp/viewarticle.php?id=1229