Incollection,
Fluctuation and Scaling Properties for a Shear Driven Field Model
Abstract Book of the XXIII IUPAP International Conference on Statistical Physics, Genova, Italy, (9-13 July 2007)
Abstract
Fluctuation relations 1 concern general features of probability
distributions for entropy production in systems driven far from
equilibrium.
In this work we study the fluctuation properties in a system with
evolution governed by a Langevin equation for a scalar field with a
Ginzburg-Landau free energy. The system, above the critical
temperature, is maintained in a non gibbsian stationary state
through the imposition of an external shear flow.
We measure the spatial correlation of the field, the time
correlation of the stress
$$\sigma=\gamma\partial_x\varphi
\partial_y\varphid r,
$$
where $\gamma$ is the shear rate. We test the
validity of the fluctuation theorem for this quantity.
Moreover, it has been recently noted 2 that the PDF of the
dissipated power in a time interval of duration $\tau$ in this
systems presents scaling properties which relates PDFs at different
$\tau$'s and transform one into the other. We have verified that
these properties holds for our system.
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50:1645-1648 (1994)\\
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10 105 (2003)
