INDEPENDENCE PROPERTY OF THE BUSEMANN FUNCTION IN EXACTLY SOLVABLE KPZ MODELS

• 成果类型: Article
• 署名作者: Shen, Xiao
• 署名单位: Utah System of Higher Education; University of Utah
• 刊物名称: ANNALS OF APPLIED PROBABILITY
• ISSN/ISSBN: 1050-5164
• DOI: 10.1214/24-AAP2118
• 发表日期: 2025
• 页码: 458-480
• 关键词: last-passage percolation; increasing sequences; geodesics; Coalescence; Invariance; EXISTENCE; points

摘要

The study of Kadar-Parsi-Zhang (KPZ) universality class has been a subject of great interest among mathematicians and physicists over the past three decades. A notably successful approach for analyzing KPZ models is the coupling method, which hinges on understanding random growth from stationary initial conditions defined by Busemann functions. To advance in this direction, we investigate the independence property of the Busemann function across multiple directions in various exactly solvable KPZ models. These models encompass the corner growth model, the inverse-gamma polymer, Brownian last-passage percolation, the O'Connell-Yor polymer, the KPZ equation, and the directed landscape. In the context of the corner growth model, our result states that disjoint Busemann increments in different directions along a down-right path are independent, as long as their associated semi-infinite geodesics have nonempty intersections almost surely. The proof for the independence utilizes the queueing representation of the Busemann process developed by Sepp & auml;l & auml;inen et al. As an application, our independence result yields a near-optimal probability upper bound (missing by a logarithmic factor) for the rare event where the endpoint of a point-to-line inversegamma polymer is close to the diagonal.