English
Related papers

Related papers: Equatorial circular motion in a Kerr-like spacetim…

200 papers

We explore circular geodesics of neutral test particles in the gravitational field of a rotating deformed mass. The geometry around this source is described by the Quevedo-Mashhoon solution, which corresponds to a naked singularity. To this…

Approximate all-terrain spacetimes for astrophysical applications are presented. The metrics possess five relativistic multipole moments, namely mass, rotation, mass quadrupole, charge, and magnetic dipole moment. All these spacetimes…

General Relativity and Quantum Cosmology · Physics 2024-11-25 Francisco Frutos-Alfaro

We construct self-consistent equilibrium sequences of general relativistic, rotating neutron star models. Special emphasis in put on the determination of the maximum rotation frequency of such objects. Recently proposed models for the…

Astrophysics · Physics 2011-05-23 G. F. Burgio , H. -J. Schulze , F. Weber

Extreme mass-ratio inspirals detectable by the future Laser Interferometer Space Antenna provide a unique way to test general relativity and fundamental physics. Motivated by this possibility, here we study in detail the EMRI dynamics in…

General Relativity and Quantum Cosmology · Physics 2020-07-22 Gabriel Andres Piovano , Andrea Maselli , Paolo Pani

We present firstly equation of motion for the photon coupled to Weyl tensor in a Kerr black hole spacetime and then study further the corresponding strong gravitational lensing. We find that black hole rotation makes propagation of the…

General Relativity and Quantum Cosmology · Physics 2017-05-19 Songbai Chen , Shangyun Wang , Yang Huang , Jiliang Jing , Shiliang Wang

We calculate moment of inertia of neutron star with different exotic constituents such as hyperons and (anti)kaon condensates and study its variation with mass and spin frequency. The sets of equation of state, generated within the…

High Energy Astrophysical Phenomena · Physics 2017-06-14 S. S. Lenka , P. Char , S. Banik

In the present paper we investigate self-consistently slowly rotating neutron and strange stars in R-squared gravity. For this purpose we first derive the equations describing the structure of the slowly rotating compact stars in…

General Relativity and Quantum Cosmology · Physics 2015-06-22 Kalin V. Staykov , Daniela D. Doneva , Stoytcho S. Yazadjiev , Kostas D. Kokkotas

We investigate the bound orbits of massive/massless, neutral particles and photons moving around regular black holes of Fan and Wang. For massive particles, we show the existence of stable/unstable circular orbits and the charge dependence…

General Relativity and Quantum Cosmology · Physics 2023-04-19 Kenshin Isomura , Ryotaku Suzuki , Shinya Tomizawa

Compact objects in general relativity approximately move along geodesics of spacetime. It is shown that the corrections to geodesic motion due to spin (dipole), quadrupole, and higher multipoles can be modeled by an extension of the point…

General Relativity and Quantum Cosmology · Physics 2021-04-07 Jan Steinhoff

We consider a well-known static, axially symmetric, vacuum solution of Einstein equations belonging to Weyl's class and determine the fundamental frequencies of small harmonic oscillations of test particles around stable circular orbits in…

General Relativity and Quantum Cosmology · Physics 2019-08-05 Bobir Toshmatov , Daniele Malafarina , Naresh Dadhich

The purpose of this paper is twofold. First, we introduce a geometric approach to study the circular orbit of a particle in static and spherically symmetric spacetime based on Jacobi metric. Second, we apply the circular orbit to study the…

General Relativity and Quantum Cosmology · Physics 2020-06-29 Zonghai Li , Guodong Zhang , Ali Övgün

Extreme-mass-ratio-inspiral (EMRI) is one of the most important sources for the future space-borne gravitational wave detectors. In such kind of systems, the compact objects usually orbit around the central supermassive black holes with…

General Relativity and Quantum Cosmology · Physics 2021-08-11 Chen Zhang , Wen-Biao Han , Shu-Cheng Yang

The motion of compact binaries is influenced by the spin of their components starting at the 1.5 post-Newtonian (PN) order. On the other hand, in the large mass ratio limit, the spin of the lighter object appears in the equations of motion…

General Relativity and Quantum Cosmology · Physics 2025-05-26 Vojtěch Witzany , Viktor Skoupý , Leo C. Stein , Sashwat Tanay

We study the motion of test particles in the gravitational field of a rotating and deformed object within the framework of the adiabatic theory. For this purpose, the Hartle-Thorne metric written in harmonic coordinates is employed in the…

We investigated universal relations for compact stars rotating at the Keplerian (mass-shedding) limit, which is highly relevant for understanding the rapidly rotating objects formed in the aftermath of a neutron star-neutron star merger.…

High Energy Astrophysical Phenomena · Physics 2025-10-15 Pion Sudarshan Yeasin , Stefanos Tsiopelas , Armen Sedrakian , Jia-Jie Li

In this paper we compute general-relativistic polytropic models simulating rigidly rotating, pulsating neutron stars. These relativistic compact objects, with a radius of $\sim 10 \, \mathrm{km}$ and mass between $\sim 1.4$ and $3.2$ solar…

General Relativity and Quantum Cosmology · Physics 2014-10-14 Vassilis Geroyannis , Eleftheria Tzelati

In this paper, we investigate the photon orbits around a Kerr-like black hole in Einstein-Bumblebee gravity, where Lorentz symmetry is spontaneously broken. By solving the Hamilton-Jacobi equation, we derive a sixth-order polynomial that…

General Relativity and Quantum Cosmology · Physics 2025-07-08 Shi-Yu Li , Song-Shan Luo , Zhong-Wen Feng

We study theoretically the quantum motion of a neutron in a horizontal wave-guide in the gravitational field of the Earth. The wave-guide in question is equipped with a mirror below and a rough absorber above. We show that such a system…

We compute the radiation emitted by a particle on the innermost stable circular orbit of a rapidly spinning black hole both (a) analytically, working to leading order in the deviation from extremality and (b) numerically, with a new…

General Relativity and Quantum Cosmology · Physics 2015-09-30 Samuel E. Gralla , Achilleas P. Porfyriadis , Niels Warburton

We examine the evolution, under gravitational radiation reaction, of slightly eccentric equatorial orbits of point particles around Kerr black holes. Our method involves numerical integration of the Sasaki-Nakamura equation. It is…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Daniel Kennefick