Corberi Federico
Dipartimento di Fisica "E. R. Caianiello" and INFN, Gruppo Collegato di Salerno, and CNISM, Unità di Salerno, Università di Salerno, via Giovanni Paolo II 132, 84084 Fisciano (SA), Italy.
Phys Rev E. 2017 Mar;95(3-1):032136. doi: 10.1103/PhysRevE.95.032136. Epub 2017 Mar 24.
We study the evolution leading to (or regressing from) a large fluctuation in a statistical mechanical system. We introduce and study analytically a simple model of many identically and independently distributed microscopic variables n_{m} (m=1,M) evolving by means of a master equation. We show that the process producing a nontypical fluctuation with a value of N=∑{m=1}^{M}n{m} well above the average 〈N〉 is slow. Such process is characterized by the power-law growth of the largest possible observable value of N at a given time t. We find similar features also for the reverse process of the regression from a rare state with N≫〈N〉 to a typical one with N≃〈N〉.
我们研究统计力学系统中导致大波动（或从大波动衰退）的演化过程。我们引入并通过解析方法研究了一个简单模型，该模型包含许多相同且独立分布的微观变量(n_{m})（(m = 1, M)），这些变量通过主方程进行演化。我们表明，产生一个非典型波动，其值(N = \sum_{m = 1}^{M}n_{m})远高于平均值(\langle N\rangle)的过程是缓慢的。这种过程的特征是在给定时间(t)，(N)的最大可能可观值呈幂律增长。我们发现，从(N\gg\langle N\rangle)的罕见状态回归到(N\simeq\langle N\rangle)的典型状态的反向过程也有类似特征。
