English
Related papers

Related papers: A new formal solution of the radiative transfer in…

200 papers

We demonstrate how one can describe explicitly the present arbitrariness in solutions of relativistic wave equations in external electromagnetic fields of special form. This arbitrariness is connected to the existence of a transformation,…

High Energy Physics - Theory · Physics 2009-11-07 V. G. Bagrov , M. C. Baldiotti , D. M. Gitman , I. V. Shirokov

We derive a grey linear diffusion equation for photons with respect to inertial (or lab-frame) space and time, using asymptotic analysis in 1D planar geometry. The solution of the equation is the comoving radiation energy density. Our…

High Energy Astrophysical Phenomena · Physics 2026-02-12 Ryan T. Wollaeger , Jim E. Morel , Kendra P. Long , Mathew A. Cleveland , Robert B. Lowrie

It is proved that the class of stable interatomic potentials admits an exact representation in the form of a finite or infinite superposition of Yukawa potentials. An auxiliary scalar field is introduced to describe the dynamics of a system…

Statistical Mechanics · Physics 2022-02-01 A. Yu. Zakharov , V. V. Zubkov

We simulate convection near the solar surface, where the continuum optical depth is of order unity. Hence, to determine the radiative heating and cooling in the energy conservation equation, we must solve the radiative transfer equation…

Astrophysics · Physics 2007-05-23 Robert Stein , Aake Nordlund

Using the methods of general relativity Lindquist derived the radiative transfer equation that is correct to all orders in v/c. Mihalas developed a method of solution for the important case of monotonic velocity fields with spherically…

Solar and Stellar Astrophysics · Physics 2014-11-20 E. Baron , Bin Chen , P. H. Hauschildt

The Lagrangian formalism is used to derive covariant equations that are suitable for use in continuously distributed matter in curved spacetime. Special attention is given to theoretical representation, in which the Lagrangian and its…

General Physics · Physics 2025-02-19 Sergey G. Fedosin

A new numerical method to solve an inverse source problem for the radiative transfer equation involving the absorption and scattering terms, with incomplete data, is proposed. No restrictive assumption on those absorption and scattering…

Numerical Analysis · Mathematics 2019-04-02 Alexey V. Smirnov , Michael V. Klibanov , Loc H. Nguyen

Many astrophysical phenomena exhibit relativistic radiative flows. While velocities in excess of $v \sim 0.1c$ can occur in these systems, it has been common practice to approximate radiative transfer to $\cO(v/c)$. In the case of neutrino…

Astrophysics · Physics 2007-05-23 Christian Y. Cardall , Eric J. Lentz , Anthony Mezzacappa

We study the well-posedness and regularity theory for the Radiative Transfer equation in the peaked regime posed in the half-space. An average lemma for the transport equation in the half-space is stablished and used to generate interior…

Analysis of PDEs · Mathematics 2020-08-11 Ricardo Alonso , Edison Cuba

We introduce a non-exponential radiative framework that takes into account the local spatial correlation of scattering particles in a medium. Most previous works in graphics have ignored this, assuming uncorrelated media with a uniform,…

Graphics · Computer Science 2018-05-14 Adrian Jarabo , Carlos Aliaga , Diego Gutierrez

Alkali-metal atomic vapors are the foundation of an ever-growing range of applications, driven by a comprehensive understanding of their interaction with light. In particular, many models have been developed which characterize this…

To facilitate the study of black hole fueling, star formation, and feedback in galaxies, we outline a method for treating the radial forces on interstellar gas due to absorption of photons by dust grains. The method gives the correct…

Astrophysics of Galaxies · Physics 2015-06-04 G. S. Novak , J. P. Ostriker , L. Ciotti

Observations and magnetohydrodynamic simulations of solar and stellar atmospheres reveal an intermittent behavior or steep gradients in physical parameters, such as magnetic field, temperature, and bulk velocities. The numerical solution of…

Solar and Stellar Astrophysics · Physics 2019-03-22 Gioele Janett

Accurate accounting of particle number and 4-momentum in radiative transfer may be facilitated by the use of transport equations that allow transparent conversion between volume and surface integrals in both spacetime and momentum space.…

Astrophysics · Physics 2016-11-09 Christian Y. Cardall

The construction of exact solutions for radiative transfer in a plane-parallel medium has been addressed by Hemsch and Ferziger in 1972 for a partial frequency redistribution model of the formation of spectral lines consisting in a linear…

Solar and Stellar Astrophysics · Physics 2024-10-31 Hélène Frisch

It is well known that Lagrangian dynamical systems naturally arise in describing wave front dynamics in the limit of short waves (which is called pseudoclassical limit or limit of geometrical optics). Wave fronts are the surfaces of…

Differential Geometry · Mathematics 2007-05-23 Ruslan Sharipov

We solve a weakly singular integral equation by Laplace transformation over a finite interval of R. The equation is transformed into a Cauchy integral equation, whose resolution amounts to solving two Fredholm integral equations of the…

Astrophysics · Physics 2007-05-23 B. Rutily , L. Chevallier

The fields used to describe the influence of masses and electric charges are generally accepted to propagate at the speed of light from their sources. To obtain these fields for a moving charge which are consistent with special relativity,…

General Physics · Physics 2021-06-15 Aran O'Hare

In this paper we present a pedestrian review of the theoretical fact that all relativistic wave equations possess solutions of arbitrary velocities $0 \leq v < \infty$. We discuss some experimental evidences of $v \geq c$ transmission of…

Popular Physics · Physics 2007-05-23 J. E. Maiorino , W. A. Rodrigues

We study the problem of the instability of inhomogeneous radiation universes in quadratic lagrangian theories of gravity written as a system of evolution equations with constraints. We construct formal series expansions and show that the…

General Relativity and Quantum Cosmology · Physics 2021-04-21 Spiros Cotsakis , Dimitrios Trachilis