  Correlations in fluids in nonequilibrium steady states are long ranged.
Hence, finite-size effects have important consequences in the nonequilibrium
thermodynamics of fluids. One consequence is that nonequilibrium temperature
fluctuations induce nonequilibrium Casimir-like pressures proportional to the
square of the temperature gradient. Hence, fluctuations cause a breakdown of
the concept of local thermal equilibrium. Furthermore, transport coefficients
become dependent on boundary conditions and on gravity. Thus nonequilibrium
fluctuations affect some traditional concepts in nonequilibrium thermodynamics.

Statistical Mechanics;Mesoscale and Nanoscale Physics