Giovanni Jona Lasinio Universita di Roma “La Sapienza”
On quasi-static transformations of diffusive systems, renormalized work and all that
For diffusive systems a theory of quasi static transformations of stationary states has been developed as a byproduct of the macroscopic fluctuation theory. In particular a notion of renormalized work has been introduced which in a quasi static transformation is equal to the variation of equilibrium free energy ΔF evaluated on these states. In addition a formula has been obtained relating ΔF to hydrodynamics. This formula implies the existence of an exact 1-form in the functional variables (E,λ), E the external field and λ the chemical potential, and introduces in a dissipative context an equivalence of transformations between fixed stationary states which recalls Clausius approach to entropy. Clausius formulated the second law of thermodynamics as a principle of equivalence of transformations and entropy provides the equivalence-value (Aequivalenzwerth) of a transformation.
Video of the lecture