Colloquium on May 26st, 2008Udo Seifert Universität Stuttgart Stochastic thermodynamics Stochastic thermodynamics provides a conceptual framework for describing small systems embedded in a heat bath and mechanically or chemically driven to nonequilibrium. Both the first law and entropy production can be consistently defined along single trajectories. An infinity of integral fluctuation theorems hold, among which the Jarzynski relation and the one on total entropy production are prominent ones [1]. After briefly reviewing and illustrating these foundations using a driven colloidal particle as paradigm, I will present within this scheme our recent work concerning (i) optimal finitetime processes [2], (ii) efficiency of stochastic heat engines and molecular motors at maximum power [3] and (iii) extended fluctuationdissipationtheorems (FDTs) and a generalized Einstein relation [4]. [1] U. Seifert, PRL 95: 040602, 2005. 


