Topological effects on the thermodynamics of open quantum systems*

The thermodynamics of open quantum systems coupled to topological fields is analyzed. Thermodynamic state functions of an open quantum system are defined based on a partition of Hilbert/Fock space, rather than a partition of the corresponding operators. This distinction is crucial, not only due to long-range interactions, but also due to uniquely quantum mechanical action at a distance. Both the Aharonov-Bohm effect for systems of charged particles and the Aharonov-Casher effect for systems of neutral spin-1/2 particles are considered. A proper treatment of the work done by the topological fields is necessary to ensure that the entropy and internal energy of the system are state functions, and to avoid thermodynamic paradoxes.