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C Cattuto

Publications and source records attributed to C Cattuto.

4 recordsLinked to original sources
PubMed2006

Fluctuation-induced casimir forces in granular fluids.

We numerically investigate the behavior of driven noncohesive granular media and find that two fixed large intruder particles, immersed in a sea of small particles, experience, in addition to a short-range depletion force, a long-range repulsive force. The observed long-range interaction is fluctuation-induced and we propose a mechanism similar to the Casimir effect that generates it: The hydrodynamic fluctuations are geometrically confined between the intruders, producing an unbalanced renormalized pressure. An estimation based on computing the possible Fourier modes explains the repulsive force and is in qualitative agreement with the simulations.

Biomechanical Phenomena↗
PubMed2004

Ordering phenomena in cooling granular mixtures.

We report two phenomena, induced by dynamical correlations, that occur during the free cooling of a two-dimensional mixture of inelastic hard disks. First, we show that, due to the onset of velocity correlations, the ratio of the kinetic energies associated with the two species changes from the value corresponding to the homogeneous cooling state to a value approximately given by the mass ratio m(1)/m(2) of the two species. Second, we report a novel segregation effect that occurs in the late stage of cooling, where interconnected domains appear. Spectral analysis of the composition field reveals the emergence of a growing characteristic length.

Journal Article↗
PubMed2001

Driven kinks in discrete chains: phonon damping.

Phonon radiation is shown numerically to damp the motion of a relativistically driven straight phi(4) soliton, even in the extremely weak discreteness limit. At higher discreteness, the soliton mobility is characterized by a discontinuous dependence on the driving force; jumps are related to phonon and breather-radiation thresholds. Moreover, the speed of a frictionless soliton cannot be lowered below a certain threshold value, or else it might get trapped between two adjacent chain sites.

Journal Article↗