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A system of two gravitating bodies floating around a restricted region of strong gravitational field is investigated. We consider two concentric spherically symmetric timelike shells spatially constrained by a perfectly reflecting inner and…

General Relativity and Quantum Cosmology · Physics 2023-12-22 Takafumi Kokubu

Coherent structures, such as solitary waves, appear in many physical problems, including fluid mechanics, optics, quantum physics, and plasma physics. A less studied setting is found in geophysics, where highly viscous fluids couple to…

Pattern Formation and Solitons · Physics 2008-01-04 Gideon Simpson , Michael I. Weinstein

Relativistic numerical cosmology is most often based either on the exact solutions of the Einstein equations, or perturbation theory, or weak-field limit, or the BSSN formalism. The Silent Universe provides an alternative approach to…

Cosmology and Nongalactic Astrophysics · Physics 2017-12-08 Krzysztof Bolejko

The general world model for homogeneous and isotropic universe has been roposed. For this purpose, we introduce a global and fiducial system of reference (world reference frame) constructed on a 5-dimensional space-time that is embedding…

Astrophysics · Physics 2008-03-04 Chan-Gyung Park

In our current best cosmological model, the vast majority of matter in the Universe is dark, consisting of yet undetected, non-baryonic particles that do not interact electro-magnetically. So far, the only significant evidence for dark…

Cosmology and Nongalactic Astrophysics · Physics 2020-09-09 Jenny Wagner

Within the closed universe, we obtain the amplitude and frequency of gravitational waves in the terms of discrete wave numbers, wave propagation time, and cosmological constant using the deviation equation in the first-order perturbed…

General Relativity and Quantum Cosmology · Physics 2021-05-27 Jafar Khodagholizadeh , Amir H. Abbassi , Ali Vahedi , Komeil Babaei

The general relativistic dynamics of a wide class of self-interacting, self-gravitating homogeneous scalar fields models is analyzed. The class is characterized by certain general conditions on the scalar field potential, which include both…

Classical Analysis and ODEs · Mathematics 2007-05-23 R. Giambò , F. Giannoni , G. Magli

We investigate the prospects for probing asymmetric dark matter models through their gravitational wave signatures. We concentrate on a theory extending the Standard Model gauge symmetry by a non-Abelian group, under which leptons form…

High Energy Physics - Phenomenology · Physics 2023-01-03 Bartosz Fornal , Erika Pierre

It is proved that an inhomogeneous medium whose boundary contains a weakly singular point of arbitrary order scatters every incoming wave. Similarly, a compactly supported source term with weakly singular points on the boundary always…

Analysis of PDEs · Mathematics 2021-12-03 Long Li , Guanghui Hu , Jiansheng Yang

Adaptive SPH and N-body simulations were carried out to study the evolution of the equilibrium structure of dark matter halos that result from the gravitational instability and fragmentation of cosmological pancakes. Such halos resemble…

Astrophysics · Physics 2009-11-06 Marcelo Alvarez , Paul R. Shapiro , Hugo Martel

We discuss the possibility of a dimensional reduction of the Einstein equations in S3 black-hole lattices. It was reported in previous literature that the evolution of spaces containing curves of local, discrete rotational and reflection…

General Relativity and Quantum Cosmology · Physics 2015-10-02 Mikołaj Korzyński , Ian Hinder , Eloisa Bentivegna

The uniqueness and rigidity theorems assert that the asymptotically flat, vacuum, stationary rotating black hole solution in general relativity must be the Kerr solution, exhibiting novel symmetries such as axisymmetry and circularity. In…

General Relativity and Quantum Cosmology · Physics 2024-12-13 Rajes Ghosh , Akash K Mishra , Sudipta Sarkar

We describe an explicit in time, finite-difference code designed to simulate black holes by using the excision method. The code is based upon the harmonic formulation of the Einstein equations and incorporates several features regarding the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Bela Szilagyi , Denis Pollney , Luciano Rezzolla , Jonathan Thornburg , Jeffrey Winicour

We demonstrate that a complete class of flat-band lattices with underlying commutative local symmetries exhibit a locally fragmented Hilbert space. The equitable partition theorem ensures distinct parities for the compact localized states…

Statistical Mechanics · Physics 2025-04-11 Eloi Nicolau , Anselmo M. Marques , Ricardo G. Dias , Verònica Ahufinger

Compact objects evolving in an astrophysical environment experience a gravitational drag force known as dynamical friction. We present a multipole-frequency decomposition to evaluate the orbit-averaged energy and angular momentum…

Astrophysics of Galaxies · Physics 2025-09-22 Gali Eytan , Vincent Desjacques , Yonadav Barry Ginat

The cascade relaxation of a polarized vacuum in the expanding Universe is a chain of evolutionary epochs of decreasing its density with the exit of dominant fields (each in its own time) from the initial zero states to nonzero values, from…

General Relativity and Quantum Cosmology · Physics 2025-06-05 V. N. Lukash , E. V. Mikheeva

The known canonical quantum theory of a spherically symmetric pure (Schwarzschild) gravitational system describes isolated black holes by plane waves exp(-iMc^2\tau/\hbar) with respect to their continuous masses M and the proper time \tau…

General Relativity and Quantum Cosmology · Physics 2010-11-19 H. A. Kastrup

We introduce and study a family of lattice equations which may be viewed either as a strongly nonlinear discrete extension of the Gardner equation, or a non-convex variant of the Lotka-Volterra chain. Their deceptively simple form supports…

Pattern Formation and Solitons · Physics 2021-08-11 Philip Rosenau , Arkady Pikovsky

We define a family of spacetimes representing isolated black holes exhibiting remarkable universal properties which are natural generalizations from stationary spacetimes. They admit a well defined notion of surface gravity k_H. This…

General Relativity and Quantum Cosmology · Physics 2017-05-12 Carlos Kozameh , Osvaldo Moreschi , Alejandro Perez

We present an unified approach for the study of idealized gravitational compact objects like wormholes and horizonless stars, here simulated by the presence of boundary conditions at a deeply inner wall. At classical level, namely…

General Relativity and Quantum Cosmology · Physics 2019-11-07 L. Sebastiani , L. Vanzo , S. Zerbini
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