Hydrodynamic fluctuations

It turns out that fluctuations in fluids in nonequilibrium states are always spatially long ranged. This phenomenon was first predicted by IPST Professors Theodore R. Kirkpatrick and J. Robert Dorfman in collaboration with E.G.D. Cohen at Rockefeller University. The long-ranged nature of hydrodynamic fluctuations in nonequilibrium is caused by a coupling between hydrodynamic modes through any thermodynamic or velocity gradient. It is known that thermal fluctuations in fluids in thermodynamic equilibrium can be described by fluctuating hydrodynamics originally developed by Landau. In our laboratory light-scattering experiments in fluids with a temperature gradient and in polymer solutions with a concentration gradient have convincingly demonstrated the validity of fluctuating hydrodynamics for describing fluctuations in nonequilibrium states as well. These nonequilibrium fluctuations are long ranged and extend over the entire system. As a consequence they are affected by the presence of gravity and by confinement. We are collaborating with experimentalists pursuing these gravity and confinement effects both on earth and in space. The confinement effects also cause a new type of fluctuation-induced Casimir-like force in liquids in nonequilibrium states.

Book Review by David Cannell: Hydrodynamic fluctuations in fluids and fluid mixtures

Book Review by Dick Bedeaux: Hydrodynamic fluctuations in fluids and fluid mixtures

Book Review by Leopoldo S. Garcia-Colin : Hydrodynamic fluctuations in fluids and fluid mixtures