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The gravitational lensing effect at higher order under weak-field approximation is believed to be important to distinguish black holes and other compact objects such as wormholes. The deflection angle of a generic wormhole is difficult to…

General Relativity and Quantum Cosmology · Physics 2023-08-02 Tingqi Cai , Hyat Huang , Zun Wang , Mian Zhu

The deflection angle of a light ray can be arbitrarily large near a light sphere. The time-symmetrical shape of light curves of a pair of light rays reflected by a light sphere of a lens object does not depend on the details of the lens…

General Relativity and Quantum Cosmology · Physics 2017-04-14 Naoki Tsukamoto

A modified Hayward black hole is a nonsingular black hole. It is proposed to form when the pressure generated by quantum gravity can stop matter's collapse as the matter reaches Planck density. Strong deflection gravitational lensing…

General Relativity and Quantum Cosmology · Physics 2017-05-02 Shan-Shan Zhao , Yi Xie

We have investigated the gravitational lensing by two wormholes, viz., Janis-Newman-Winnicour (JNW) wormhole and Ellis wormhole. The deflection angle in the strong field limit is calculated and various lens parameters of two wormholes are…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Tushar Kanti Dey , Surajit Sen

We discuss the contribution to the characteristic lensing quantities, i.e. the deflection angle and Einstein radius, due to the higher order terms (e.g. the gravitomagnetic terms) considered in the lens potential. The cases we analyze are…

Astrophysics · Physics 2011-01-27 Salvatore Capozziello , Virginia Re

We systematically investigate the microlensing effect of charged spherically symmetric wormhole, where the light source is remote from the throat. Remarkably, there will be at most three images by considering the charge part. We study all…

General Relativity and Quantum Cosmology · Physics 2023-01-23 Lei-Hua Liu , Mian Zhu , Wentao Luo , Yi-Fu Cai , Yi Wang

In this paper, we use the strong field limit approach to investigate the gravitational lensing properties of braneworld black holes. Applying this method to the supermassive black hole at the centre of our galaxy, the lensing observables…

Astrophysics · Physics 2009-11-10 Richard Whisker

This study deals with the new class of embedded wormhole solutions in the background of general relativity. Two newly calculated wormhole solutions satisfy all the required properties. All the energy conditions are discussed through their…

General Relativity and Quantum Cosmology · Physics 2024-06-17 Niyaz Uddin Molla , Himanshu Chaudhary , Ujjal Debnath , G. Mustafa , S. K. Maurya

Stable massless wormholes are theoretically interesting in their own right as well as for astrophysical applications, especially as galactic halo objects. Therefore, the study of gravitational lensing observables for such objects is of…

General Relativity and Quantum Cosmology · Physics 2023-11-17 R. F. Lukmanova , G. Y. Tuleganova , R. N. Izmailov , K. K. Nandi

Horizonless compact objects with light rings (or photon spheres) are becoming increasingly popular in recent years for several reasons. In this paper, we show that a horizonless object such as a wormhole of Morris-Thorne type can have two…

General Relativity and Quantum Cosmology · Physics 2019-01-01 Rajibul Shaikh , Pritam Banerjee , Suvankar Paul , Tapobrata Sarkar

It has been shown that a noncommutative-geometry background may be able to support traversable wormholes. This paper discusses the possible detection of such wormholes in the outer regions of galactic halos by means of gravitational…

General Relativity and Quantum Cosmology · Physics 2016-08-16 Peter K. F. Kuhfittig

For the last decade, the gravitational lensing in the strong gravitational field has been studied eagerly. It is well known that, for the lensing by a black hole, infinite number of Einstein rings are formed by the light rays which wind…

General Relativity and Quantum Cosmology · Physics 2012-12-07 Naoki Tsukamoto , Tomohiro Harada , Kohji Yajima

The multiple images of lensed quasars provide evidence on the mass distribution of the lensing galaxy. The lensing invariants are constructed from the positions of the images, their parities and their fluxes. They depend only on the…

Astrophysics · Physics 2009-11-06 C. Hunter , N. W. Evans

Gravitational lensing is a good probe into the topological structure of dark gravitating celestial objects. In this paper, we investigate the light curve of a light ray that passes through the throat of an Ellis wormhole, the simplest…

General Relativity and Quantum Cosmology · Physics 2017-01-25 Naoki Tsukamoto , Tomohiro Harada

We investigate strong gravitational lensing by two static black hole models (Model-1 and Model-2) within the Effective Quantum Gravity (EQG) framework, characterized by mass $M$ and parameter $\zeta$. For $\zeta = 0$, they reduce to the…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-17 Yiyang Wang , Amnish Vachher , Qiang Wu , Tao Zhu , Sushant G. Ghosh

We consider gravitational lensing under a weak-field approximation and in a strong deflection limit by a Bronnikov-Kim wormhole with the same metric as the one of a wormhole which has been suggested in Einstein-Dirac-Maxwell theory. The…

General Relativity and Quantum Cosmology · Physics 2022-03-08 Naoki Tsukamoto

Here the gravitational lensing in strong field limit of a Schwarzschild black hole with a solid deficit angle owing to global monopole within the context of the $f(R)$ gravity theory is investigated. We obtain the expressions of deflection…

General Relativity and Quantum Cosmology · Physics 2015-09-23 Jingyun Man , Hongbo Cheng

Gravitational lensing by traversable Lorentzian wormholes is a ew possibility which is analyzed here in the strong field limit. Wormhole solutions are considered in the Einstein minimally coupled theory and in the brane world model. The…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Kamal Kanti Nandi , Yuan-Zhong Zhang , Alexander V. Zakharov

Lensing in a spherically symmetric and static spacetime is considered, based on the lightlike geodesic equation without approximations. After fixing two radius values r_O and r_S, lensing for an observation event somewhere at r_O and static…

General Relativity and Quantum Cosmology · Physics 2010-02-23 Volker Perlick

We provide an in depth study of the theoretical peculiarities that arise in effective negative mass lensing, both for the case of a point mass lens and source, and for extended source situations. We describe novel observational signatures…

General Relativity and Quantum Cosmology · Physics 2016-08-16 Margarita Safonova , Diego F. Torres , Gustavo E. Romero