Quantum and classical approaches in statistical physics: some basic inequalities and game theoretic interpretation
Lev Sakhnovich
Abstract
We present some basic inequalities between the classical and quantum values of free energy, entropy and mean energy. The extremal principles (e.g., the Fermat's principle of least time and the least action principle), which remain central in modern physics, are formulated in terms of one physical value. Using our inequalities, we give a game theoretic interpretation of the interaction of three physical values, namely, free energy, entropy and mean energy. Such approach is inspired by Neumann--Morgenstern and Nash game theories. According to these game theories, the transition from the deterministic strategy (classical mechanics) to probabilistic strategy (quantum mechanics) increases the winning for all players. In the second part of the paper, we simultaneously derive the quasi-classical limits for four cases, that is, for $h{\to}0$, $T{\to}\infty$, $\omega{\to}0$, and $N{\to}\infty,$ where $h$ is the Planck constant, $T$ is the absolute temperature, $\omega$ is the frequency of an oscillator, and $N$ is the degree of freedom of a system. We note that only the first case is usually considered in quantum physics. The second case was studied initially by M. Planck and the third case by A.~Einstein.