The Equilibrium Statistical Model of Economic Systems using Concepts and Theorems of Statistical Physics

Economic systems are similar with physic systems for their large number of individuals and the exist of equilibrium. In this paper, we present a model applying the equilibrium statistical model in economic systems. Consistent with statistical physics, we define a series of concepts, such as economic temperature, economic pressure, economic potential, wealth and population. Moreover, we suggest that these parameters show pretty close relationship with the concepts in economy. This paper presents related concepts in the equilibrium economic model and constructs significant theorems and corollaries, which is derived from the priori possibility postulate, getting theorems including the equilibrium theorem between open systems, the distribution theorem of wealth and population along with related corollaries. More importantly, we demonstrate a method constructing optimal density of states, optimizing a macroscopic parameter depending on need to get the distribution of density of states utilizing the variation method, which is significant for the development of a society. In addition, we calculate a simple economic system as an example, indicating that the system occupied mostly by the middle class could develop stably and soundly, explaining the reason for resulting distributions of macroscopic parameters.