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Related papers: Gravitational Lensing by Polytropic Wormholes

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It is generally agreed that the acceleration of the Universe can best be explained by the presence of dark or phantom energy. The equation of state of the latter shows that the null energy condition is violated. Such a violation is the…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Mubasher Jamil , Peter K. F. Kuhfittig , Farook Rahaman , Sk. A Rakib

In this study, we found a new traversable wormhole solution in the framework of a bumblebee gravity model. With these types of models, the Lorentz symmetry violation arises from the dynamics of a bumblebee vector field that is non-minimally…

General Relativity and Quantum Cosmology · Physics 2019-01-30 Ali Övgün , Kimet Jusufi , İzzet Sakallı

The present paper deals with some wormhole solutions which are obtained by taking two different shape functions along with zero tidal force. For obtaining wormhole solutions, anisotropic fluid and a equation of state $p_t=-\frac{a}{\rho}$…

General Relativity and Quantum Cosmology · Physics 2021-08-31 Bikram Ghosh , Saugata Mitra

In strong gravitational lensing, the multiple images we see correspond to light rays that leave the source in slightly different directions. If the source emission is anisotropic, the images may differ from conventional lensing predictions…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Rosalba Perna , Charles R. Keeton

Propagating gravitational waves (GWs) can encounter a massive object (lens) whose gravitational radius is comparable to the wavelength of the GWs (wave-optics regime). The resulting `microlensed' signal contains imprints about the…

General Relativity and Quantum Cosmology · Physics 2025-12-23 Gopalkrishna Prabhu , Uddeepta Deka , Sumanta Chakraborty , Shasvath J. Kapadia

In this thesis, we investigate traversable wormhole spacetimes within the context of a covariant generalization of Einstein's General Relativity, namely the energy-momentum squared gravity, denoted as $f\left(R,T_{ab}T^{ab}\right)$. Here,…

General Relativity and Quantum Cosmology · Physics 2024-12-13 Nailya Ganiyeva

Continuous gravitational waves are analogous to monochromatic light and therefore could be used to detect wave effects like interference or diffraction. This would be possible with strongly lensed gravitational waves. This article reviews…

General Relativity and Quantum Cosmology · Physics 2022-02-02 Marek Biesiada , Sreekanth Harikumar

With the increase in the number of observed gravitational wave (GW) signals, detecting strongly lensed GWs by galaxies has become a real possibility. Lens galaxies also contain microlenses (e.g., stars and black holes), introducing further…

Astrophysics of Galaxies · Physics 2022-10-05 Ashish Kumar Meena , Anuj Mishra , Anupreeta More , Sukanta Bose , Jasjeet Singh Bagla

We present wormhole solutions to Horava non-relativistic gravity theory in vacuum. We show that, if the parameter $\lambda$ is set to one, transversable wormholes connecting two asymptotically de Sitter or anti-de Sitter regions exist. In…

High Energy Physics - Theory · Physics 2011-01-17 Marcelo Botta-Cantcheff , Nicolas Grandi , Mauricio Sturla

In these lectures I give an overview of gravitational lensing, concentrating on theoretical aspects, including derivations of some of the important results. Topics covered include the determination of surface mass densities of intervening…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-08 Alan Heavens

We extend the theory of weak gravitational lensing to cosmologies with generalized gravity, described in the Lagrangian by a generic function depending on the Ricci scalar and a non-minimal coupled scalar field. We work out the generalized…

Astrophysics · Physics 2009-11-10 Viviana Acquaviva , Carlo Baccigalupi , Francesca Perrotta

This paper investigates the novel phenomenon of gravitational lensing experienced by gravitational waves traveling past a Schwarzschild black hole perturbed by a specific, first-order, polar gravitational wave. We utilize the Gauss-Bonnet…

General Relativity and Quantum Cosmology · Physics 2024-08-23 Reggie C. Pantig , Ali Övgün

We present a static, spherically symmetric, traversable wormhole solution to multimetric gravity which is sustained by only non-exotic matter, i.e., matter which satisfies all energy conditions. The possibility of this solution arises from…

General Relativity and Quantum Cosmology · Physics 2014-04-11 Manuel Hohmann

In this article, we study the possibility of sustaining a static and spherically symmetric traversable wormhole geometries admitting conformal motion in Einstein gravity, which presents a more systematic approach to search a relation…

General Relativity and Quantum Cosmology · Physics 2017-02-01 Piyali Bhar , Farook Rahaman , Tuhina Manna , Ayan Banerjee

This study aims to investigate the viability of a viable logarithmic f(R) gravity for inflation in giving wormhole solutions. We consider a static and spherically symmetric spacetime and two different shape functions. We found that the…

General Relativity and Quantum Cosmology · Physics 2022-06-27 Yusmantoro , Rian Julianto

In this paper, we explore higher-dimensional asymptotically flat wormhole geometries in the framework of Gauss-Bonnet (GB) gravity and investigate the effects of the GB term, by considering a specific radial-dependent redshift function and…

General Relativity and Quantum Cosmology · Physics 2015-04-06 Mohammad Reza Mehdizadeh , Mahdi Kord Zangeneh , Francisco S. N. Lobo

In this work we extend the approach used in [Emanuel Gallo and Osvaldo M. Moreschi, Phys. Rev. D 83, 12 083007 (2011)] to the study of weak gravitational lensing in a plasma medium. First, we present expressions for the deflection angle and…

General Relativity and Quantum Cosmology · Physics 2019-08-14 Gabriel Crisnejo , Emanuel Gallo , José R. Villanueva

We investigate in detail the weak-field gravitational lensing of a relativistic neutral massive particle induced by a regular black-bounce-Schwarzschild black hole proposed by Simpson and Visser. Starting with the calculation of the…

General Relativity and Quantum Cosmology · Physics 2024-09-04 Guansheng He , Yi Xie , Chunhua Jiang , Wenbin Lin

The well-known problem of wormholes in general relativity (GR) is the necessity of exotic matter, violating the Weak Energy Condition (WEC), for their support. This problem looks easier if, instead of island-like configurations, one…

General Relativity and Quantum Cosmology · Physics 2020-01-08 K. A. Bronnikov , S. V. Bolokhov , M. V. Skvortsova

In this paper we study gravitational lensing by STU black holes. We considered extremal limit of two special cases of zero-charged and one-charged black holes, and obtain the deflection angle. We find that the black hole charge increases…

General Relativity and Quantum Cosmology · Physics 2014-01-03 Hassan Saadat
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