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Related papers: Ray-tracing and polarized radiative transfer in Ge…

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The discussion regarding the numerical integration of the polarized radiative transfer equation is still open and the comparison between the different numerical schemes proposed by different authors in the past is not fully clear. Aiming at…

Solar and Stellar Astrophysics · Physics 2017-09-06 Gioele Janett , Edgar S. Carlin , Oskar Steiner , Luca Belluzzi

If a clock, mathematically modeled by a parametrized timelike curve in a general-relativistic spacetime, is given, the radar method assigns a time and a distance to every event which is sufficiently close to the clock. Several geometric…

General Relativity and Quantum Cosmology · Physics 2015-05-13 Volker Perlick

Liquid crystals allow for the real-time control of the polarization of light. We describe and provide some experimental examples of the types of general polarization transformations, including universal polarization transformations, that…

Optics · Physics 2018-05-14 Alicia Sit , Lambert Giner , Ebrahim Karimi , Jeff S. Lundeen

The linear perturbation theory of inhomogeneous reionization (LPTR) has been developed as an analytical tool for predicting the global ionized fraction and large-scale power spectrum of ionized density fluctuations during reionization. In…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-05 Yi Mao , Anson D'Aloisio , Benjamin D. Wandelt , Jun Zhang , Paul R. Shapiro

We consider the problem of determination of a magnetic field from three dimensional polarimetric neutron tomography data. We see that this is an example of a non-Abelian ray transform and that the problem has a globally unique solution for…

Analysis of PDEs · Mathematics 2019-10-21 Naeem M. Desai , William R. B. Lionheart , Morten Sales , Markus Strobl , Søren Schmidt

The gravitational metric tensor implies a variable dielectric tensor of vacuum around gravitational matter. The curved spacetime in general relativity is then associated with a polarizable vacuum. It is found that the number density of the…

General Physics · Physics 2009-03-24 Xing-Hao Ye

We come back to the analytical solution of the standard transfer problem in a stellar atmosphere. It consists in solving the radiative transfer equation in a homogeneous and isothermal plane-parallel atmosphere, with light scattering taken…

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

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

We give an analytic solution for the propagation of polarised radiation through a homogeneous water body. As corollaries we derive the vector bidirectional reflectance distribution function at the bottom of an infinitely deep water body and…

Optics · Physics 2019-12-04 Andrew Corbett

A meshless method is presented to solve the radiative transfer equation in the even parity formulation of the discrete ordinates method in complex 2D and 3D geometries. Prediction results of radiative heat transfer problems obtained by the…

Computational Physics · Physics 2018-07-10 Cheng-An Wang , Hamou Sadat , Vital Le dez , Denis Lemonnier

The solution of a nonlinear diffusion equation is numerically investigated using the generalized Fourier transform method. This equation includes fractal dimensions and power-law dependence on the radial variable and on the diffusion…

Computational Physics · Physics 2019-11-12 Jie Yao , Cameron L. Williams , Fazle Hussain , Donald J. Kouri

There is ongoing interest in adopting various tools and ideas from general relativity for optical applications and the study of light propagation through natural or engineered media. Here, the covariant kinematics of light propagating…

General Relativity and Quantum Cosmology · Physics 2017-11-15 Robert T. Thompson , Mohsen Fathi

We develop a unified scattering approach to dynamical Casimir problems which can be applied to both accelerating boundaries, as well as dispersive objects in relative motion. A general (trace) formula is derived for the radiation from…

Quantum Physics · Physics 2013-01-14 Mohammad F. Maghrebi , Ramin Golestanian , Mehran Kardar

Context. Numerical solutions to transfer problems of polarized radiation in solar and stellar atmospheres commonly rely on stationary iterative methods, which often perform poorly when applied to large problems. In recent times, stationary…

Numerical Analysis · Mathematics 2021-12-08 Pietro Benedusi , Gioele Janett , Luca Belluzzi , Rolf Krause

This article presents an on-line tool (rttools.irap.omp.eu) and its accompanying software ressources for the numerical solution of basic radiation transfer out of local thermodynamic equilibrium (LTE). State-of-the-art stationary iterative…

Instrumentation and Methods for Astrophysics · Physics 2015-12-09 J. Lambert , F. Paletou , E. Josselin , J. -M. Glorian

A full symmetry classification is given for models of energy transport in radiant plasma when the mass density is spatially variable and the diffusivity is nonlinear. A systematic search for conservation laws also leads to some potential…

Mathematical Physics · Physics 2015-06-18 P. Broadbridge , N. M. Ivanova

Birefringent crystals are extensively used to manipulate polarized light. The generalized transfer matrix developed allows efficient calculation of the full polarization state of light transmitted through and reflected by a stack of…

Optics · Physics 2014-03-25 Thomas Essinger-Hileman

Models for the observational appearance of astrophysical black holes rely critically on accurate general-relativistic ray tracing and radiation transport to compute the intensity measured by a distant observer. In this paper, we illustrate…

General Relativity and Quantum Cosmology · Physics 2023-10-05 Gabriele Bozzola , Chi-kwan Chan , Vasileios Paschalidis

X-ray radiation from neutron stars manifests itself in a variety of settings. Isolated pulsars, and magnetars both exhibit quasi-thermal persistent soft X-ray emission from their surfaces. Transient magnetospheric bursts from magnetars and…

High Energy Astrophysical Phenomena · Physics 2025-02-21 Matthew G. Baring , Kun Hu , Hoa Dinh Thi

Interpolation of data represented in curvilinear coordinates and possibly having some non-trivial, typically Riemannian or semi-Riemannian geometry is an ubiquitous task in all of physics. In this work we present a covariant generalization…

Instrumentation and Methods for Astrophysics · Physics 2019-09-25 Pauli Pihajoki , Matias Mannerkoski , Peter H. Johansson