English
Related papers

Related papers: Energy-momentum diffusion from spacetime discreten…

200 papers

Since microscopic velocity diffusion can be incorporated into general relativity in a consistent way, we study cosmological background solutions when the diffusion phenomena takes place in an expanding universe. Our focus here relies on the…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-10 Hermano Velten , Simone Calogero

The Lorentz gas, a point particle making mirror-like reflections from an extended collection of scatterers, has been a useful model of deterministic diffusion and related statistical properties for over a century. This survey summarises…

Chaotic Dynamics · Physics 2017-06-29 Carl P. Dettmann

I propose a model of mutually interacting particles on an M-dimensional unit sphere. I derive the dynamics of the particles by extending the dynamics of the Kuramoto-Sakaguchi model. The dynamics include a natural-frequency matrix, which…

Adaptation and Self-Organizing Systems · Physics 2014-02-10 Takuma Tanaka

The article describes a new approach to obtaining the energy-momentum tensor of electromagnetic field in medium without the use of Maxwell's equations and Poynting theorem. The energy-momentum tensor has new qualities and consequences. Its…

Classical Physics · Physics 2017-04-13 Yurii A. Spirichev

The dynamics of a point charged particle which is driven by a uniform external electric field and moves in a medium of elastic scatterers is investigated. Using rudimentary approaches, we reproduce, in one dimension, the known results that…

Statistical Mechanics · Physics 2009-10-28 P. L. Krapivsky , S. Redner

In this work, we focus on the behavior of a single passive Brownian particle in a suspension of passive particles with short-range repulsive interactions and a larger self-diffusion coefficient. While the forces affecting the…

Statistical Mechanics · Physics 2023-04-26 Deborah Schwarcz , Stanislav Burov

This paper is aimed to elaborate the problem of energy-momentum in General Relativity. In this connection, we use the prescriptions of Einstein, Landau-Lifshitz, Papapetrou and M\"{o}ller to compute the energy-momentum densities for two…

General Relativity and Quantum Cosmology · Physics 2014-11-17 M. Sharif , Tasnim Fatima

We consider a generalization of the classical nonrelativistic St\"{o}rmer problem, describing the motion of charged particles in a purely magnetic dipole field, by taking into account the effects of the dissipation, assumed to be of…

High Energy Astrophysical Phenomena · Physics 2026-04-28 Tiberiu Harko , Gabriela Raluca Mocanu

According to the classical Einstein-Maxwell theory of gravity and electromagnetism, a light-wave traveling in empty space-time is accompanied by a gravitational field of the pp-type. Therefore point masses are scattered by a light wave,…

High Energy Physics - Phenomenology · Physics 2015-05-13 J. W. van Holten

We revisit the classical theory of a relativistic massless charged point particle with spin and interacting with an external electromagnetic field. In particular, we give a proper definition of its kinetic energy and its total energy, the…

High Energy Physics - Theory · Physics 2017-12-27 Ivan Morales , Bruno Neves , Zui Oporto , Olivier Piguet

The Brownian motion of a point particle induced by quantum vacuum fluctuations of a massless real scalar field in Einstein's universe is studied. By assuming the small displacement condition, the dispersion in the momentum and position of a…

General Relativity and Quantum Cosmology · Physics 2024-04-09 E. J. B. Ferreira , H. F. Santana Mota

We investigate bright and dark solitons with anomalous or normal dispersion and under transverse harmonic confinement. In matter waves, positive atomic mass implies anomalous dispersion (kinetic spreading) while negative mass gives normal…

Other Condensed Matter · Physics 2009-11-11 L. Salasnich , A. Parola , L. Reatto

The momentum of light inside ponderable media has an electromagnetic part and a mechanical part. The local and instantaneous density of the electromagnetic part of the momentum is given by the Poynting vector divided by the square of the…

Optics · Physics 2012-08-07 Masud Mansuripur

A diffusion process for charge distributions in a phase space is examined. The corresponding charge moves in a force field and under an action of a random field. There are the diffusion motions for coordinates and for momenta. In our model,…

Mathematical Physics · Physics 2008-03-19 E. M. Beniaminov

A nonlinear Lorentz invariant kinetic diffusion equation is introduced, which is consistent with the conservation laws of particles number, energy and momentum. The equilibrium solution converges to the Maxwellian density in the Newtonian…

General Relativity and Quantum Cosmology · Physics 2025-11-14 Simone Calogero

For a substance diffusing on a curved surface, we obtain an explicit relation valid for very small values of the time, between the local concentration, the diffusion coefficient, the intrinsic spatial curvature and the time. We recover the…

Biological Physics · Physics 2009-11-10 J. Balakrishnan

We propose that dark matter is not yet another new particle in nature, but that it is a remnant of quantum gravitational effects on known fields. We arrive at this possibility in an indirect and surprising manner: by considering retarded,…

High Energy Physics - Theory · Physics 2015-11-11 Mehdi Saravani , Siavash Aslanbeigi

We investigate the evolution of a light impurity particle in a Lorentz gas where the background atoms are in thermal equilibrium. As in the standard Lorentz gas, we assume that the particle is negligibly light in comparison with the…

Statistical Mechanics · Physics 2013-05-29 L. D'Alessio , P. L. Krapivsky

The modified Dirac equations describing massless and massive spin-1/2 particles violating the Lorentz invariance are considered. The equation for massless fermions with varying speed is formulated in the 16-component first-order form. The…

High Energy Physics - Phenomenology · Physics 2014-03-07 S. I. Kruglov

In general relativity one of the most fundamental issues consists in defining a generally acceptable definition for the energy-momentum density. As a consequence, many coordinate-dependent definitions have been presented, whereby some of…

General Relativity and Quantum Cosmology · Physics 2015-05-30 Irina Radinschi , Theophanes Grammenos , Andromahi Spanou