Distribution of Equilibrium Free Energies in a Thermodynamic System with Broken Ergodicity  

作　　者：ZHOU Hai-Jun LI Kang 

机构地区：[1]Institute of Theoretical Physics, the Chinese Academy of Sciences, Beijing 100080, China

出　　处：《Communications in Theoretical Physics》2008年第3期659-664,共6页理论物理通讯（英文版）

基　　金：supported by National Natural Science Foundation of China under Grant No.10774150

摘　　要：At low temperatures the configurational phase space of a macroscopic complex system （e.g., a spin-glass） of N - 10^23 interacting particles may split into an exponential number Ωs - exp（const × N） of ergodic sub-spaces （thermodynamic states）. It is usually assumed that the equilibrium collective behavior of such a system is determined by its ground thermodynamic states of the minimal free-energy density, and that the equilibrium free energies follow the distribution of exponentied decay. But actually for some complex systems, the equilibrium free-energy values may follow a Gaussian distribution within an intermediate temperature range, and consequently their equilibrium properties are contributed by excited thermodynamic states. Based on this analysis, the re-weighting parameter y in the cavity approach of spin-glasses is easily understood. Depending on the free-energy distribution, the optimal y can either be equal to or be strictly less than the inverse temperature β.

关 键 词：free-energy distribution SPIN-GLASS thermodynamic state cavity approach broken ergodicity 

分 类 号：O55[理学—热学与物质分子运动论]