Extended irreversible thermodynamics and non-equilibrium temperature

• Main Authors: Casas-Vazquez, Jose', Jou, David
• Format: Article
• Language: English
• Published: Accademia Peloritana dei Pericolanti 2008-02-01
• Series: Atti della Accademia Peloritana dei Pericolanti : Classe di Scienze Fisiche, Matematiche e Naturali
• Online Access: http://dx.doi.org/10.1478/C1S0801006

We briefly review the concept of non-equilibrium temperature from the perspectives of extended irreversible thermodynamics, fluctuation theory, and statistical mechanics. The relations between different proposals are explicitly examined in two especially simple systems: an ideal gas in steady shear flow and a forced harmonic oscillator in a thermal bath. We examine with special detail temperatures related to the average molecular kinetic energy along different spatial directions, to the average configurational energy, to the derivative of the entropy with respect to internal energy, to fluctuation-dissipation relation and discuss their measurement.