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The quantum version of the Boltzmann transport equation (Wigner-Boltzmann equation) is a quite useful tool to investigate the effects of energy dissipation in quantum systems. Numerical approaches uses to be employed in order to stablish a…

Statistical Mechanics · Physics 2017-09-19 A. R. Fernandes Nt. , L. F. Santos

We consider the linear dissipative Boltzmann equation describing inelastic interactions of particles with a fixed background. For the simplified model of Maxwell molecules first, we give a complete spectral analysis, and deduce from it the…

Analysis of PDEs · Mathematics 2009-02-20 Bertrand Lods , Clément Mouhot , Giuseppe Toscani

For the first time exact analytical solutions to the eikonal equations in (1+1) dimensions with a refractive index being a saturated function of intensity are constructed. It is demonstrated that the solutions exhibit collapse; an explicit…

Mathematical Physics · Physics 2010-07-15 Martin E. Garcia , Vladimir F. Kovalev , Larisa L. Tatarinova

We present an analytical closed form expression, which gives a good approximate propagator for diffusion on the sphere. Our formula is the spherical counterpart of the Gaussian propagator for diffusion on the plane. While the analytical…

Statistical Mechanics · Physics 2016-10-05 Abhijit Ghosh , Joseph Samuel , Supurna Sinha

We describe an exact and highly efficient numerical algorithm for solving a special but important class of convection-diffusion equations. These equations occur in many problems in physics, chemistry, or biology, and they are usually hard…

Computational Physics · Physics 2019-03-27 Narain Karedla , Jan Christoph Thiele , Ingo Gregor , Jörg Enderlein

We obtain an approximate global stationary and axisymmetric solution of Einstein's equations which can be thought as a simple two layers star model: a self-gravitating ball built up by two layers of perfect fluid having different linear…

General Relativity and Quantum Cosmology · Physics 2018-06-12 Alfred Molina , Eduardo Ruiz

We study the diffusive limit approximation for a nonlinear radiative heat transfer system that arises in the modeling of glass cooling, greenhouse effects and in astrophysics. The model is considered with the reflective radiative boundary…

Analysis of PDEs · Mathematics 2021-10-12 Mohamed Ghattassi , Xiaokai Huo , Nader Masmoudi

Inspired by a recently conjectured universal bound for thermo-electric diffusion constants in quantum critical, strongly coupled systems and relying on holographic analytical computations, we investigate the possibility of formulating…

High Energy Physics - Theory · Physics 2015-07-30 Andrea Amoretti , Alessandro Braggio , Nicodemo Magnoli , Daniele Musso

The derivation of suitable analytical models is an important step for the design and analysis of molecular communication systems. However, many existing models have limited applicability in practical scenarios due to various simplifications…

Emerging Technologies · Computer Science 2019-11-28 Maximilian Schäfer , Wayan Wicke , Werner Haselmayr , Rudolf Rabenstein , Robert Schober

We propose a very simple one dimensional analytically solvable model for understanding the problem of electronic relaxation of molecules in solution. This problem is modeled by a particle diffusing under the influence of parabolic potential…

Statistical Mechanics · Physics 2020-03-23 Swati Mudra , Aniruddha Chakraborty

We develop a thermal description for photon modes within the context of bouncing universe. Within this study, we start with a Lorentz-breaking dispersion relation which accounts for modified Friedmann equations with a bounce solution. We…

High Energy Physics - Theory · Physics 2022-01-27 A. A. Araújo Filho , A. Yu. Petrov

We consider black hole spacetimes that are holographically dual to strongly coupled field theories in which spatial translations are broken explicitly. We discuss how the quasinormal modes associated with diffusion of heat and charge can be…

High Energy Physics - Theory · Physics 2018-04-04 Aristomenis Donos , Jerome P. Gauntlett , Vaios Ziogas

We consider self-similar approximations of nonlinear hyperbolic systems in one space dimension with Riemann initial data and general diffusion matrix. We assume that the matrix of the system is strictly hyperbolic and the diffusion matrix…

Analysis of PDEs · Mathematics 2008-12-16 K. T. Joseph , Philippe G. LeFloch

To determine the electron heat flux density on macroscopic scales, the most widely used approach is to solve a diffusion equation through a multi-group technique. This method is however restricted to transport induced by temperature…

Motivated by recent applications of superdiffusive transport models to shock-accelerated particle distributions in the heliosphere, we solve analytically a one-dimensional fractional diffusion-advection equation for the particle density. We…

Space Physics · Physics 2015-06-23 Yuri E. Litvinenko , Frederic Effenberger

We investigate in this article the long-time behaviour of the solutions to the energy-dependant, spatially-homogeneous, inelastic Boltzmann equation for hard spheres. This model describes a diluted gas composed of hard spheres under…

Analysis of PDEs · Mathematics 2012-07-18 Thomas Rey

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

We model the expansion of an interacting atomic Bose-Einstein condensate in a disordered lattice with a nonlinear diffusion equation normally used for a variety of classical systems. We find approximate solutions of the diffusion equation…

The stochastic formalism of inflation allows us to describe the scalar-field dynamics in a non-perturbative way. The correspondence between the diffusion and Schr\"{o}dinger equations makes it possible to exhaustively construct analytical…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-25 Masazumi Honda , Ryusuke Jinno , Koki Tokeshi

An analytical representation for the spatial and temporal dynamics of the simplest of the diffusions -- Bronwian diffusion in an homogeneous slab geometry, with radial symmetry -- is presented. This representation is useful since it…

Classical Physics · Physics 2015-01-22 E. J. Nunes-Pereira