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Related papers: Applying Modified Gravity (MOG) to the Lensing and…

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JWST has made several surprising discoveries, underscored by the `too early' appearance of well-formed galaxies and supermassive black holes. It recently also uncovered a compact galaxy (JWST-ER1g) associated with a complete Einstein ring…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-14 Fulvio Melia

The recent years witnessed a surge of interest of the lensing of the black holes arising from general as well as other modified theories of gravity due to the experimental data available from the EHT results. The EHT may open a new door…

General Relativity and Quantum Cosmology · Physics 2022-01-19 Md Sabir Ali , Shagun Kaushal

In this paper, we investigate the gravitational lensing effect and the shadow around a Schwarzschild-like black hole in metric-affine bumblebee gravity, which leads to the Lorentz symmetry breaking. We first present a generalized formalism…

General Relativity and Quantum Cosmology · Physics 2024-09-20 Xiao-Jun Gao

A modified gravitational theory explains early universe and late time cosmology, galaxy and galaxy cluster dynamics. The modified gravity (MOG) theory extends general relativity (GR) by three extra degrees of freedom: a scalar field $G$,…

General Relativity and Quantum Cosmology · Physics 2020-10-30 J. W. Moffat

I report discovery of a new galaxy-scale gravitational lens system, identified using public data from the MaNGA survey, as part of a systematic search for lensed background line-emitters. The lens is SDSS J170124.01+372258.0, a giant…

Astrophysics of Galaxies · Physics 2016-10-26 Russell J. Smith

We present a gravitational lensing analysis of the galaxy cluster Abell 1689, incorporating measurements of the weak shear, flexion, and strong lensing induced in background galaxies. This is the first time that a shapelet technique has…

Astrophysics · Physics 2011-02-11 Adrienne Leonard , David M. Goldberg , Jason L. Haaga , Richard Massey

We identify a strong lensing galaxy in the cluster IRC 0218 (also known as XMM-LSS J02182$-$05102) that is spectroscopically confirmed to be at $z=1.62$, making it the highest-redshift strong lens galaxy known. The lens is one of the two…

Weyl's conformal gravity theory, which is considered as a compelling alternative to general relativity theory, has been claimed to describe the observed flat rotation curve feature of spiral galaxies without the need of invoking dark…

General Relativity and Quantum Cosmology · Physics 2023-07-12 Shubhrangshu Ghosh , Mahasweta Bhattacharya , Yanzi Sherpa , Arunava Bhadra

Gravitational waves (GWs) may be magnified or de-magnified due to lensing. This phenomenon will bias the distance estimation based on the matched filtering technique. Via the multi-sphere ray-tracing technique, we study the GW magnification…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-21 Xikai Shan , Chengliang Wei , Bin Hu

(Abridged) We measure the mass distribution of galaxy cluster Abell 1689 within 0.3 Mpc/h_70 of the cluster centre using its strong lensing effect on 32 background galaxies. The multiple images are based on those of Broadhurst et al. 2005…

Astrophysics · Physics 2009-11-11 A. Halkola , S. Seitz , M. Pannella

We apply the modified acceleration law obtained from Einstein gravity coupled to a massive skew symmetric field, F_{\mu\nu\lambda}, to the problem of explaining X-ray galaxy cluster masses without exotic dark matter. Utilizing X-ray…

Astrophysics · Physics 2007-11-22 J. R. Brownstein , J. W. Moffat

How does the appearance of a strongly lensed system change if a gravitational wave is produced by the lens? In this work we address this question by considering a supermassive black hole binary at the center of the lens emitting…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-29 Leonardo Giani , Cullan Howlett , Tamara M. Davis

In the braneworld scenario, the four dimensional effective Einstein equation has extra terms which arise from the embedding of the 3-brane in the bulk. These non-local effects, generated by the free gravitational field of the bulk, may…

Astrophysics · Physics 2016-08-30 T. Harko , K. S. Cheng

Measurements of the properties of gravitational lenses have the power to tell us what sort of universe we live in. The brightest known radio Einstein ring/gravitational lens PKS 1830-211 (Jauncey et al., 1991), whilst obscured by our Galaxy…

A method to calculate light curves of the gravitational microlensing of the Ellis wormhole is derived in the weak-field limit. In this limit, lensing by the wormhole produces one image outside the Einstein ring and one other image inside.…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 F. Abe

Gravitational lensing represents a powerful tool to estimate the cosmological pa- rameters and the distribution of dark matter. I will describe the main observable quantities, concentrating on strong lensing, that manifests its effect…

Astrophysics · Physics 2007-05-23 C. Tortora

(abridged) We utilize existing imaging and spectroscopic data for the galaxy clusters MS2137-23 and Abell 383 to present improved measures of the distribution of dark and baryonic material in the clusters' central regions. Our method, based…

Astrophysics · Physics 2009-11-13 D. J. Sand , T. Treu , R. S. Ellis , G. P. Smith , J-P Kneib

We study the Mass Discrepancy-Acceleration Relation (MDAR) of 57 elliptical galaxies by their Einstein rings from the Sloan Lens ACS Survey (SLACS). The mass discrepancy between the lensing mass and the baryonic mass derived from population…

Astrophysics of Galaxies · Physics 2017-09-20 Yong Tian , Chung-Ming Ko

Hubble Space Telescope imaging of the galaxy cluster Abell 1689 has revealed an exceptional number of strongly lensed multiply-imaged galaxies, including high-redshift candidates. Previous studies have used this data to obtain the most…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Jose M. Diego , T. Broadhurst , N. Benitez , K. Umetsu , D. Coe , I. Sendra , M. Sereno , L. Izzo , G. Covone

Strong gravitational lensing by galaxies in MOdified Newtonian Dynamics (MOND) has until now been restricted to spherically symmetric models. These models were able to account for the size of the Einstein ring of observed lenses, but were…

Astrophysics · Physics 2009-06-23 HuanYuan Shan , Martin Feix , Benoit Famaey , HongSheng Zhao