Original article at: http://www.math.washington.edu/~ejpecp/viewarticle.php?id=1880

Competing Particle Systems and the Ghirlanda-Guerra Identities

Louis-Pierre Arguin, Courant Institute, NYU

Abstract

Competing particle systems are point processes on the real line whose configurations X can be ordered decreasingly and evolve by increments which are functions of correlated Gaussian variables. The correlations are intrinsic to the points and quantified by a matrix Q={qij}. Quasi-stationary systems are those for which the law of (X,Q) is invariant under the evolution up to translation of X. It was conjectured by Aizenman and co-authors that the matrix Q of robustly quasi-stationary systems must exhibit a hierarchical structure. This was established recently, up to a natural decomposition of the system, whenever the set SQ of values assumed by qij is finite. In this paper, we study the general case where SQ may be infinite. Using the past increments of the evolution, we show that the law of robustly quasi-stationary systems must obey the Ghirlanda-Guerra identities, which first appear in the study of spin glass models. This provides strong evidence that the above conjecture also holds in the general case. In addition, it yields an alternative proof of a theorem of Ruzmaikina and Aizenman for independent increments.

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=1880