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Pair distributions of fluids confined between two surfaces at close distance are of fundamental importance for a variety of physical, chemical, and biological phenomena, such as interactions between macromolecules in solution, surface…

Soft Condensed Matter · Physics 2013-11-01 Kim Nygård , Sten Sarman , Roland Kjellander

We show that it is possible to obtain credible static anisotropic spherically symmetric matter configurations starting from known density profiles and satisfying a nonlocal equation of state. These particular types of equation of state…

General Relativity and Quantum Cosmology · Physics 2015-06-25 H. Hernandez , L. A. Nunez

We apply lattice Boltzmann methods to study the segregation of binary fluid mixtures under oscillatory shear flow in two dimensions. The algorithm allows to simulate systems whose dynamics is described by the Navier-Stokes and the…

Soft Condensed Matter · Physics 2009-11-07 Aiguo Xu , G. Gonnella , A. Lamura

A particular choice of the time function in the recently presented spherical solution by Dadhich [1] leads to a singularity free cosmological model which oscillates between two regular states. The energy-stress tensor involves anisotropic…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Naresh Dadhich , A. K. Raychaudhuri

We study systematically stationary solutions to the coupled Vlasov and Poisson equations which have `self-similar' or scaling symmetry in phase space. In particular, we find analytically {\it all} spherically symmetric distribution…

Astrophysics · Physics 2015-06-24 R. N. Henriksen , Lawrence M. Widrow

The behavior of perturbations is studied in cosmological models which consist of two different homogeneous regions connected in a spherical shell boundary. The junction conditions for the metric perturbations and the displacements of the…

Astrophysics · Physics 2009-11-10 Kenji Tomita

We develop a mean-field model to examine the stability of a `quasi-2D suspension' of elongated particles embedded within a viscous membrane. This geometry represents several biological and synthetic settings, and we reveal mechanisms by…

Fluid Dynamics · Physics 2024-05-22 Harishankar Manikantan

We study a spherical, self-gravitating fluid model, which finds applications in cosmic structure formation. We argue that since the system features nonlinearity and gravity-induced dispersion, the emergence of solitons becomes possible. We…

Pattern Formation and Solitons · Physics 2024-02-21 G. N. Koutsokostas , S. Sypsas , O. Evnin , T. P. Horikis , D. J. Frantzeskakis

A microscopic model which has proven useful in describing amphiphilic aggregates as inhomogeneities of a fluid is extended here to study the case of a two component surfactant mixture. We have chosen an effective interaction between the…

Soft Condensed Matter · Physics 2007-05-23 D. Duque , P. Tarazona , E. Chacon

We propose a model to study symmetric binary fluids, based in the mesoscopic molecular simulation technique known as multiparticle collision, where space and state variables are continuous while time is discrete. We include a repulsion rule…

Adaptation and Self-Organizing Systems · Physics 2016-06-22 C. Echeverria , K. Tucci , O. Alvarez-Llamoza , E. E. Orozco-Guillén , M. Morales , M. G. Cosenza

The local balance equations for the density, momentum, and energy of a dilute gas of elastic or inelastic hard spheres, strongly confined between two parallel hard plates are obtained. The starting point is a Boltzmann-like kinetic…

Statistical Mechanics · Physics 2020-04-22 J. Javier Brey , P. Maynar , M. I. García de Soria

The Rayleigh-Taylor instability plays an important role in the dynamics of several astronomical objects, in particular, in supernovae (SN) evolution. In this paper we develop an analytical approach to study the stability analysis of…

Plasma Physics · Physics 2008-11-26 Xavier Ribeyre , Ludovic Hallo , Vladimir Tikhonchuk , Serge Bouquet , Javier Sanz

Comparison of a few simple models of fluid and solid membranes illustrates how shear stresses can arise from a bending energy through a coupling between curvature and surface stresses, a feature incidental to the fluid or solid nature of…

Soft Condensed Matter · Physics 2025-06-03 S. Dharmavaram , J. A. Hanna

Non-ideal fluids are generally subject to the occurrence of non-isotropic pressure tensors, whose determination is fundamental in order to characterize their dynamical and thermodynamical properties. This requires the implementation of…

Plasma Physics · Physics 2023-06-22 Claudio Cremaschini , Jiří Kovář , Zdeněk Stuchlík , Massimo Tessarotto

The present work deals with dynamics of gravitational collapse with cylindrical symmetry as developed by Misner and Sharp. The interior collapsing anisotropic cylindrical perfect fluid is matched to an exterior vacuum cylindrically…

General Relativity and Quantum Cosmology · Physics 2016-03-08 Sanjukta Chakraborty , Subenoy Chakraborty

This work investigates the long time asymptotic behavior of some inhomogeneous non-linear Schr\"odinger type equations. We give sharp a threshold of scattering versus non-scattering of mass solutions, depending on the source term. This work…

Analysis of PDEs · Mathematics 2025-01-03 B. Ayed. Sabria , T. Saanouni

It is now well-established that mechanical equilibrium in athermal disordered solids gives rise to anisotropic spatial correlations of the coarse-grained stress field that decay in space as $1/r^d$, where $r$ is the distance from the…

Soft Condensed Matter · Physics 2021-02-03 Edan Lerner

We consider the periodic problem for two-fluid non-isentropic Euler-Maxwell systems in plasmas. By means of suitable choices of symmetrizers and an induction argument on the order of the time-space derivatives of solutions in energy…

Analysis of PDEs · Mathematics 2018-08-15 Yue-Hong Feng , Xin Li , Shu Wang

In this talk we show a stiff fluid solution of the Einstein equations for a cylindrically symmetric spacetime. The main features of this metric are that it is non-separable in comoving coordinates for the congruence of the worldlineS of the…

General Relativity and Quantum Cosmology · Physics 2009-06-01 L. Fernández-Jambrina

We present new numerical cosmological solutions of the Einstein Field Equations. The spacetime is spherically symmetric with a source of dust and radiation approximated as a perfect fluid. The dust and radiation are necessarily non-comoving…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-14 Woei Chet Lim , Marco Regis , Chris Clarkson