A relation is obtained between the parameter describing the irreversible response of a driven dissipative system and the spontaneous fluctuations of the thermodynamic extensive parameters of the system in equilibrium. The development given in this paper extends the theorem, previously proven in the statistical mechanical domain, to the macroscopic thermodynamic domain.

• Received 24 January 1952

DOI:https://doi.org/10.1103/PhysRev.86.702