6 research outputs found
Non equilibrium statistical physics with fictitious time
Problems in non equilibrium statistical physics are characterized by the
absence of a fluctuation dissipation theorem. The usual analytic route for
treating these vast class of problems is to use response fields in addition to
the real fields that are pertinent to a given problem. This line of argument
was introduced by Martin, Siggia and Rose. We show that instead of using the
response field, one can, following the stochastic quantization of Parisi and
Wu, introduce a fictitious time. In this extra dimension a fluctuation
dissipation theorem is built in and provides a different outlook to problems in
non equilibrium statistical physics.Comment: 4 page
Noise induced oscillations in non-equilibrium steady state systems
We consider effect of stochastic sources upon self-organization process being
initiated with creation of the limit cycle. General expressions obtained are
applied to the stochastic Lorenz system to show that departure from equilibrium
steady state can destroy the limit cycle at certain relation between
characteristic scales of temporal variation of principle variables. Noise
induced resonance related to the limit cycle is found to appear if the fastest
variations displays a principle variable, which is coupled with two different
degrees of freedom or more.Comment: 11 pages, 4 figures. Submitted to Physica Script
Critical Casimir force in the superfluid phase: effect of fluctuations
We have considered the critical Casimir force on a He film below and
above the bulk point. We have explored the role of fluctuations
around the mean field theory in a perturbative manner, and have substantially
improved the mean field result of Zandi et al [Phys. Rev. E {\bf 76}, 030601(R)
(2007)]. The Casimir scaling function obtained by us approaches a universal
constant () for .Comment: The term at the Fig.2-caption in
the published version should be read as $\frac{1}{4b\xi_0^4k_BT_\lambda}