English
Related papers

Related papers: Tomography of Collisionless Stellar Systems

200 papers

A model of static boson-fermion star with spherical symmetry based on the scalar-tensor theory of gravity with massive dilaton field is investigated numerically. Since the radius of star is \textit{a priori} an unknown quantity, the…

Numerical Analysis · Mathematics 2025-10-20 T. L. Boyadjiev , M. D. Todorov , P. P. Fiziev , S. S. Yazadjiev

In this paper alternative method for real-time 3D model rasterization is given. Surfaces are drawn in perspective-map space which acts as a virtual camera lens. It can render single-pass 360{\deg} angle of view (AOV) image of unlimited…

Graphics · Computer Science 2020-10-20 Jakub Maksymilian Fober

We construct the general spherically symmetric and self-similar solution of the Einstein-Vlasov system (collisionless matter coupled to general relativity) with massless particles, under certain regularity conditions. Such solutions have a…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Jose M. Martin-Garcia , Carsten Gundlach

We consider a particular approach to the regularization of the inverse problem of computerized tomography. This approach is based on notions pertaining to Fourier synthesis. It refines previous contributions, in which the preprocessing of…

Optimization and Control · Mathematics 2014-01-30 Pierre Maréchal , Abdelhadi Elasmai

This article gives the construction and complete classification of all three-dimensional spherical manifolds, and orders them by decreasing volume, in the context of multiconnected universe models with positive spatial curvature. It…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Evelise Gausmann , Roland Lehoucq , Jean-Pierre Luminet , Jean-Philippe Uzan , Jeffrey Weeks

We present an efficient and flexible method for solving the non-linear lasing equations of the steady-state ab initio laser theory. Our strategy is to solve the underlying system of partial differential equations directly, without the need…

The purpose of this material is to review the Adler Kostant Symes scheme as a theory which can be developped succesfully in different contexts. It was useful to describe some mechanical systems, the so called generalized Toda, and now it…

Mathematical Physics · Physics 2008-05-21 Gabriela P. Ovando

[Abridged] N-body simulations of collisionless collapse have offered important clues to the construction of realistic stellar dynamical models of elliptical galaxies. Understanding this idealized and relatively simple process, by which…

Astrophysics · Physics 2009-11-10 M. Trenti , G. Bertin , T. S. van Albada

Photothermal imaging is a powerful noncontact and nondestructive technique for subsurface inspection of composite materials, yet its performance is fundamentally limited by the diffusive and irreversible nature of heat transport, leading to…

Applied Physics · Physics 2026-05-06 Pengfei Zhu , Julien Lecompagnon , Philipp Daniel Hirsch , Mathias Ziegler

An analytical solution of the perturbed equations is obtained, which exists in all ergodic models of collisionless spherical stellar systems with a single length parameter. This solution corresponds to variations of this parameter, i.e.,…

Astrophysics of Galaxies · Physics 2023-11-10 Evgeny V. Polyachenko , Ilia G. Shukhman

The Schr\"odinger Method is a novel approach for modeling numerically self-gravitating, collisionless systems that may have certain advantages over N-body and phase space methods. In particular, smoothing is part of the dynamics and not…

Astrophysics · Physics 2007-05-23 George Davies , Lawrence M. Widrow

Characterizing the nonclassicality of quantum systems under minimal assumptions is an important challenge for quantum foundations and technology. Here we introduce a theory-independent method of process tomography and perform it on a…

Quantum Physics · Physics 2026-03-18 Albert Aloy , Matteo Fadel , Thomas D. Galley , Caroline L. Jones , Markus P. Mueller

In order to extract maximal information about cosmology from the large-scale structure of the Universe, one needs to use every bit of signal that can be observed. Beyond the spatial distributions of astronomical objects, the spatial…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-23 Takahiko Matsubara

Skyrmions are important topologically non-trivial fields characteristic of models spanning scales from the microscopic to the cosmological. However, the Skyrmion number can only be defined for fields with specific boundary conditions,…

Stereology allows shifting from the 3D distribution of the volumes of Poissonian Voronoi Diagrams to their 2D cross-sections. The basic assumption is that the 3D statistics of the volumes of the voids in the local Universe has a…

Cosmology and Nongalactic Astrophysics · Physics 2012-09-24 L. Zaninetti

Symmetry groups allow to transform solutions of differential equations continuously into other solutions. This property can be used for the observability analysis of infinite-dimensional systems with input and output. In this contribution,…

Optimization and Control · Mathematics 2019-05-28 Bernd Kolar , Markus Schöberl

A theoretical framework is presented which allows to quantitatively predict the final stationary state achieved by a non-neutral plasma during a process of collisionless relaxation. As a specific application, the theory is used to study…

Statistical Mechanics · Physics 2009-11-13 Yan Levin , Renato Pakter , Tarcisio N. Teles

First, we have ensured that spherical nonrotating collisionless systems collapse with almost retaining spherical configurations during initial contraction phases even if they are allowed to collapse three-dimensionally. Next, on the…

Astrophysics · Physics 2015-06-24 S. Hozumi , T. Fujiwara , Y. Kan-ya

This paper numerically investigates the feasibility of lensless zoomable holographic multiple projections to tilted planes. We have already developed lensless zoomable holographic single projection using scaled diffraction, which calculates…

An explicit full nulling scheme for cosmic shear observations is presented. It makes possible the construction of shear maps from extended source distributions for which the lens distance distribution is restricted to a definite interval.…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Francis Bernardeau , Takahiro Nishimichi , Atsushi Taruya