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We study the time-like geodesic congruences, in the space-time geometry of a Schwarzschild black hole surrounded by quintessence. The nature of effective potential along with the structure of the possible orbits for test particles in view…

General Relativity and Quantum Cosmology · Physics 2015-06-22 Rashmi Uniyal , N. Chandrachani Devi , Hemwati Nandan , K. D. Purohit

One of the main features of nonlinear electrodynamics (NED) is the existence of an effective geometry that describes the geodesic motion of photons. A detailed analysis of the properties of effective geometry is of utmost importance for a…

General Relativity and Quantum Cosmology · Physics 2026-03-19 Marco A. A. de Paula , Haroldo C. D. Lima , Pedro V. P. Cunha , Carlos A. R. Herdeiro , Luís C. B. Crispino

The scattering of light by water droplets can produce one of the most beautiful phenomena in Nature: the rainbow. This optical phenomenon has analogues in molecular, atomic and nuclear physics. Recently, rainbow scattering has been shown to…

General Relativity and Quantum Cosmology · Physics 2019-03-21 Luiz C. S. Leite , Caio F. B. Macedo , Luís C. B. Crispino

We consider scattering and capture of circular cosmic strings by a Schwarzschild black hole. Although being a priori a very simple axially symmetric two-body problem, it shows all the features of chaotic scattering. In particular, it…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Andrei V. Frolov , Arne L. Larsen

Recent observations by the Event Horizon Telescope (EHT) indicate that the shadow of the compact object at our Galaxy's center (Sgr A*) closely resembles that of a Schwarzschild black hole. However, identifying the presence and exact…

General Relativity and Quantum Cosmology · Physics 2025-12-24 Ashok B. Joshi , Vishva Patel , Parth C. Varasani

Schwarzschild black hole is the simplest black hole that is studied most in detail. Its behavior is best understood by looking at the geodesics of the particles under the influence of its gravitational field. In this paper, the focus of…

General Relativity and Quantum Cosmology · Physics 2016-11-08 Metin Arik , M. Tuna Pesen

We envisage a black hole perturbed by a force-free magnetic field (FFMF) outside and attempt to determine its structure. We suppose the metric that describes this black hole is of the static spherical type, that is Schwarzschild, and the…

General Relativity and Quantum Cosmology · Physics 2022-11-03 Haidar Sheikhahmadi

Non-commutative black holes(NCBH), due to the non-commutativity of spacetime coordinates, lead to a modification of the spacetime metric. By replacing the Dirac delta function with a Gaussian distribution, the mass is effectively smeared,…

General Relativity and Quantum Cosmology · Physics 2025-02-06 Mohammad Ali S. Afshar , Jafar Sadeghi

Recent observations of black hole shadows have revolutionized our ability to probe gravity in extreme environments. This manuscript presents a novel analytic method to calculate, in leading-order terms, the key parameters of photon sphere…

General Relativity and Quantum Cosmology · Physics 2024-06-04 Vitalii Vertogradov , Ali Övgün

We show that low-energy photon scattering from a body with radius R slightly larger than its Schwarzschild radius r_s resembles black-hole absorption. This absorption occurs via capture to one of the many long-lived, densely packed…

General Relativity and Quantum Cosmology · Physics 2014-09-26 Y. V. Stadnik , G. H. Gossel , V. V. Flambaum , J. C. Berengut

As an example of a black hole in a non-flat background a composite static spacetime is constructed. It comprises a vacuum Schwarzschild spacetime for the interior of the black hole across whose horizon it is matched on to the spacetime of…

General Relativity and Quantum Cosmology · Physics 2008-11-26 K. Rajesh Nayak , M. A. H. MacCallum , C. V. Vishveshwara

Black holes are a paradigm in nowadays physics, and are expected to be hosted at the center of galaxies. Supermassive galactic black holes are not isolated, and their surroundings play crucial roles in many observational features. The…

General Relativity and Quantum Cosmology · Physics 2016-04-04 Caio F. B. Macedo , Luiz C. S. Leite , Luís C. B. Crispino

The well-known Schwarzschild black hole was first obtained as a stationary, spherically symmetric solution of the Einstein's vacuum field equations. But until thirty years later, efforts were made for the analytic extension from the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Shu Dai , Cheng-Bo Guan

The geodesic method has played a crucial role in understanding the circular orbits generated by compact objects, culminating in the definition of the photon sphere, which was later generalized to a photon surface in arbitrary spacetimes.…

Recently, we introduced the Lorentzian-Euclidean black hole, a static and spherically symmetric solution of vacuum Einstein equations that exhibits a change in metric signature across the event horizon. In this framework, the analysis of…

General Relativity and Quantum Cosmology · Physics 2025-07-14 Salvatore Capozziello , Emmanuele Battista , Silvia De Bianchi

We study the nature of particle geodesics around a non-linear electrodynamic black hole (NLED-BH) inspired by the confinement of a heavy quark-antiquark system, which reduces to Maxwell's linear electrodynamics theory at the strong field…

General Relativity and Quantum Cosmology · Physics 2025-10-02 Hari Prasad Saikia , Mrinnoy M. Gohain , Kalyan Bhuyan

Circular photon orbit and black hole shadow are significantly important issues in physics and astronomy, and a number of breakthroughs have been witnessed in recent years. Conventionally, the stable and unstable circular photon orbits are…

General Relativity and Quantum Cosmology · Physics 2024-09-12 Chen-Kai Qiao , Ming Li

Black hole shadows are a widespread topic in astrophysics. This paper searches for an optical view of the black hole and the relationship between black hole shadow and photon sphere with curvature. We were inspired by the observations of…

General Relativity and Quantum Cosmology · Physics 2025-08-26 Ajay Kumar Sharma , Kanav Ganguly , Murli Manohar Verma

We study images of spacetimes containing continuous photon spheres (CPS). For a self-gravitating, isotropic, spherically symmetric spacetime with CPS, we find that a thin accretion disk produces images that closely resemble those of a…

General Relativity and Quantum Cosmology · Physics 2026-01-21 Long-Yue Li , Xia-Yuan Liu , Rong-Gen Cai , Yungui Gong , Wenting Zhou

The thermodynamic and spectroscopic behaviour of Schwarzschild black hole surrounded by quintessence are studied. We have derived the thermodynamic quantities and studied their behaviour for different values of quintessence parameter. We…

General Relativity and Quantum Cosmology · Physics 2013-01-14 R Tharanath , V C Kuriakose