Thermodynamic transformations |
| TYPE | Theor./Math. Physics Seminar |
| Speaker: | Prof. Gianni Jona-Lasinio |
| Affiliation: | Sapienza University of Rome |
| Parent Event: | Non-equilibrium thermodynamics via the study of large fluctuations |
| Date: | 06.11.2016 |
| Time: | 14:30 - 15:30 |
| Location: | Lewiner Seminar Room (412) |
| Abstract: | We consider the transformations of a macroscopic system from a stationary state to another state induced by varying parameters like boundary chemical potentials and/or external fields. We analyse the energy balance and observe that the work done on a system over an infinitely long time is infinite due to the energy spent to keep it out of equilibrium. Therefore the work has to be renormalized. In the macroscopic fluctuation theory this is done naturally by using a splitting of the current induced by time reversal. A Clausius type inequality holds for the renormalized work. We then discuss transformations over a long but finite interval of time and expand in powers of the inverse of time. New relationships connecting the variation of the free energy to hydrodynamics are obtained. We finally discuss optimization problems concerning the protocols of a transformation in view of a minimal dissipation of energy. |