Antunes Felipe L, Benetti Fernanda P C, Pakter Renato, Levin Yan
Instituto de Física, Universidade Federal do Rio Grande do Sul, Caixa Postal 15051, CEP 91501-970, Porto Alegre, RS, Brazil.
Phys Rev E Stat Nonlin Soft Matter Phys. 2015 Nov;92(5):052123. doi: 10.1103/PhysRevE.92.052123. Epub 2015 Nov 17.
In the thermodynamic limit, systems with long-range interactions do not relax to equilibrium, but become trapped in nonequilibrium stationary states. For a finite number of particles a nonequilibrium state has a finite lifetime, so that eventually a system will relax to thermodynamic equilibrium. The time that a system remains trapped in a quasistationary state (QSS) scales with the number of particles as N(δ), with δ>0, and diverges in the thermodynamic limit. In this paper we will explore the role of chaotic dynamics on the time that a system remains trapped in a QSS. We discover that chaos, measured by the Lyapunov exponents, favors faster relaxation to equilibrium. Surprisingly, weak chaos favors faster relaxation than strong chaos.
在热力学极限下，具有长程相互作用的系统不会弛豫到平衡态，而是会被困在非平衡稳态中。对于有限数量的粒子，非平衡态具有有限的寿命，因此最终系统会弛豫到热力学平衡态。系统被困在准稳态（QSS）的时间随粒子数按N(δ) 缩放，其中δ>0，并且在热力学极限下发散。在本文中，我们将探讨混沌动力学在系统被困在QSS的时间上所起的作用。我们发现，用李雅普诺夫指数衡量的混沌有利于更快地弛豫到平衡态。令人惊讶的是，弱混沌比强混沌更有利于更快地弛豫。
