Ergodic properties in athermal diffusion processes and its applications

2016 Fiscal Year Final Research Report

• Project/Area Number: 26800204
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Mathematical physics/Fundamental condensed matter physics
• Research Institution: Keio University
• Principal Investigator: Akimoto Takuma 慶應義塾大学, 理工学研究科(矢上), 特任准教授 (30454044)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: 異常拡散 / エルゴード特性 / 非熱的な拡散

Outline of Final Research Achievements

Purpose of our research project is to clarify ergodic properties of time-averaged mean square displacement characterizing diffusivity of systems in non-thermally driven diffusion processes, where fluctuation-dissipation relation is broken. We consider a random walk model where the jump length is coupled to the waiting time and a Brownian motion where the diffusion coefficient changes randomly with time. We analytical showed the ensemble average and the relative standard deviation of time-averaged mean square displacement as a function of the measurement time and its initial ensemble dependency.
Our works have been published in Phys. Rev. E and J. Stat. Mech. and I gave presentations on this issue in international conferences.

Free Research Field

統計物理学