Talkner Peter, Hänggi Peter
Institut für Physik, Universität Augsburg, Universitätsstraße 1, D-86159 Augsburg, Germany.
Institute of Physics, University of Silesia, 40007 Katowice, Poland.
Phys Rev E. 2016 Aug;94(2-1):022143. doi: 10.1103/PhysRevE.94.022143. Epub 2016 Aug 29.
Based on the explicit knowledge of a Hamiltonian of mean force, the classical statistical mechanics and equilibrium thermodynamics of open systems in contact with a thermal environment at arbitrary interaction strength can be formulated. Yet, even though the Hamiltonian of mean force uniquely determines the equilibrium phase space probability density of a strongly coupled open system, the knowledge of this probability density alone is insufficient to determine the Hamiltonian of mean force, needed in constructing the underlying statistical mechanics and thermodynamics. We demonstrate that under the assumption that the Hamiltonian of mean force is known, an extension of thermodynamic structures from the level of averaged quantities to fluctuating objects (i.e., a stochastic thermodynamics) is possible. However, such a construction undesirably also involves a vast ambiguity. This situation is rooted in the eminent lack of a physical guiding principle allowing us to distinguish a physically meaningful theory out of a multitude of other equally conceivable ones.
基于平均力哈密顿量的显式知识，可以构建与任意相互作用强度的热环境接触的开放系统的经典统计力学和平衡热力学。然而，尽管平均力哈密顿量唯一地确定了强耦合开放系统的平衡相空间概率密度，但仅知道这个概率密度不足以确定构建基础统计力学和热力学所需的平均力哈密顿量。我们证明，在已知平均力哈密顿量的假设下，热力学结构从平均量水平扩展到涨落对象（即随机热力学）是可能的。然而，这样的构建也不可避免地涉及到巨大的模糊性。这种情况源于明显缺乏一个物理指导原则，使我们能够从众多同样可想象的理论中区分出一个具有物理意义的理论。
