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Related papers: Radiative Transfer Along Rays in Curved Spacetimes

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We deduce the equations that describe how polarized radiation is Comptonized by a hot electron gas. Low frequencies are considered, and the equations are expanded to second order in electron velocities. Induced scattering terms are included…

Astrophysics · Physics 2009-10-31 Frode K. Hansen , Per B. Lilje

We present shape-preserving spatially accelerating electromagnetic wavepackets in curved space: wavepackets propagating along non-geodesic trajectories while recovering their structure periodically. These wavepackets are solutions to the…

Complexified Lienard-Wiechert potentials simplify the mathematics of Kerr-Newman particles. Here we constrain them by fiat to move along Bohmian trajectories to see if anything interesting occurs, as their equations of motion are not known.…

Quantum Physics · Physics 2018-10-17 Mark Davidson

A multi-branch quantum circuit is considered from the viewpoint of coherent electron or wave transport. Starting with the closed system, we give analytical conditions for the appearance of two isolated localized states out of the energy…

Statistical Mechanics · Physics 2011-09-06 Angelo Ziletti

It is generally believed that the radiation of relativistic particles in a curved magnetic field proceeds in either the synchrotron or the curvature radiation modes. In this paper we show that in strong curved magnetic fields a significant…

High Energy Astrophysical Phenomena · Physics 2015-01-22 S. R. Kelner , A. Yu. Prosekin , F. A. Aharonian

In chains of closely-spaced nanoparticles supporting surface polaritons, near-field electromagnetic coupling leads to collective effects and super-Planckian thermal radiation exchange. Researchers have primarily used two analytical…

Mesoscale and Nanoscale Physics · Physics 2019-04-19 Eric J. Tervo , Baratunde A. Cola , Zhuomin M. Zhang

Cosmic rays (CR), constrained by scattering on magnetic irregularities, are believed to propagate diffusively. But a well-known defect of diffusive approximation whereby some of the particles propagate unrealistically fast has directed…

High Energy Astrophysical Phenomena · Physics 2016-10-11 Mikhail Malkov , Roald Sagdeev

Using a so-called hemispherical model we derive a general transport equation for cosmic ray and thermal particles scattered in pitch angle by magnetic inhomogeneities in a moving collisionless plasma. The weak scattering through 90 degrees…

Astrophysics · Physics 2009-11-11 V. N. Zirakashvili

Collective orders and photo-induced phase transitions in quantum matter can evolve on timescales which are orders of magnitude slower than the femtosecond processes related to electronic motion in the solid. Quantum Boltzmann equations can…

Strongly Correlated Electrons · Physics 2021-08-11 Antonio Picano , Jiajun Li , Martin Eckstein

Gravitational redshift is discussed in the context of quantum photons propagating in curved spacetime. A brief introduction to modelling realistic photons is first presented and the effect of gravity on the spectrum computed for photons…

Albeit the past intensive research, the governing equation of anomalous diffusion which is observed for the transport of particles underground is still an open problem. In this paper, as a governing equation, the advection-diffusion…

Analysis of PDEs · Mathematics 2025-05-27 Manabu Machida

Equation describing propagation of gravitational waves (GW) over arbitrary curved space-time background is analyzed. New terms, which are absent in the conventional homogeneous and isotropic Friedmann cosmology, are found. Some examples of…

General Relativity and Quantum Cosmology · Physics 2022-05-24 E. V. Arbuzova , A. D. Dolgov , L. A. Panasenko

We present a comprehensive analytical study of radiative transfer using the method of moments and include the effects of non-isotropic scattering in the coherent limit. Within this unified formalism, we derive the governing equations and…

Earth and Planetary Astrophysics · Physics 2015-06-19 Kevin Heng , João M. Mendonça , Jae-Min Lee

Cosmic-ray transport in astrophysical environments is often dominated by the diffusion of particles in a magnetic field composed of both a turbulent and a mean component. This process, which is two-fold turbulent mixing in that the particle…

High Energy Astrophysical Phenomena · Physics 2021-12-14 P. Reichherzer , L. Merten , J. Dörner , J. Becker Tjus , M. J. Pueschel , E. G. Zweibel

Galactic transport models for cosmic rays involve the diffusive motion of these particles in the interstellar medium. Due to the large-scale structured galactic magnetic field this diffusion is anisotropic with respect to the local field…

High Energy Astrophysical Phenomena · Physics 2013-06-07 Frederic Effenberger , Horst Fichtner , Klaus Scherer , Ingo Büsching

We introduce a technique for recovering a sufficiently smooth function from its ray transform over a wide class of curves in a general region of Euclidean space. The method is based on a complexification of the underlying vector fields…

Complex Variables · Mathematics 2010-11-12 Nicholas Hoell , Guillaume Bal

Galactic cosmic ray transport relies on the existence of turbulence on scales comparable with the gyration radius of the particles and with wavenumber vector oriented along the local magnetic field. In the standard picture, in which…

High Energy Astrophysical Phenomena · Physics 2023-12-29 O. Pezzi , P. Blasi

Cosmic-ray transport in turbulent astrophysical environments remains a multifaceted problem and, despite decades of study, the impact of complex magnetic field geometry -- evident in simulations and observations -- has only recently…

Cosmic ray propagation is diffusive because of pitch angle scattering by waves. We demonstrate that if the high-amplitude magnetohydrodynamic turbulence with $\tilde B/\langle B\rangle \sim 1$ is present on top of the mean field gradient,…

High Energy Astrophysical Phenomena · Physics 2015-09-30 Mikhail V. Medvedev , Viktor V. Medvedev

The radiative transfer equation (RTE) is a cornerstone for describing the propagation of electromagnetic radiation in a medium, with applications spanning atmospheric science, astrophysics, remote sensing, and biomedical optics. Despite its…

Optics · Physics 2024-01-19 Vladimir Allaxwerdian , Dmitry V. Naumov