2009/10/08 by Hans Christian Öttinger, Hans Christian Ottinger
Computer Science · Physics and Astronomy · #Advanced Thermodynamics and Statistical Mechanics #Non-equilibrium thermodynamics #Nonlinear Dynamics and Pattern Formation #Physics #Statistical Mechanics and Entropy #Statistical physics #Theoretical physics #Thermodynamics #cond-mat.stat-mech
paper · pdf · doi:10.1007/s10955-010-9919-6
published as J Stat Phys (2010) 138: 1067-1083 · 20 pages; submitted to the Journal of Statistical Physics
arxiv created 2009/10/08 · openalex publication_date 2010/01/13 · arxiv updated 2010/11/10 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We compare two approaches to nonequilibrium thermodynamics, the two-generator bracket formulation of time-evolution equations for averages and the macroscopic fluctuation theory, for an isothermal driven diffusive system under steady state conditions. The fluctuation dissipation relations of both approaches play an important role for a detailed comparison. The nonequilibrium Helmholtz free energies introduced in these two approaches differ as a result of boundary conditions. A Fokker-Planck equation derived by projection operator techniques properly reproduces long range fluctuations in nonequilibrium steady states and offers the most promising possibility to describe the physically relevant fluctuations around macroscopic averages for time-dependent nonequilibrium systems.