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Related papers: Exploring degeneracies in modified gravity with we…

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In this manuscript, we provide a comprehensive study of gravitational lensing by dark compact objects predicted by a Modified Gravity (MOG) based on the Scalar-Vector-Tensor action, and the aim is to analyze new insights into the nature of…

General Relativity and Quantum Cosmology · Physics 2025-03-07 Nagina Rehman , Zoe C. S. Chan , Mubasher Jamil , Mustapha Azreg-Aïnou

We study the sensitivity of weak lensing by large scale structures to the evolution of dark energy. We explore a 2-parameters model of dark energy evolution, inspired by tracking quintessence models. To this end, we compute the likelihood…

Astrophysics · Physics 2008-11-26 Karim Benabed , Ludovic Van Waerbeke

We calculate deviations in cosmological observables as a function of parameters in a class of connection-based models of quantum gravity. In this theory non-trivial modifications to the background cosmology can occur due to a distortion of…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-01 Michael W. Toomey , Savvas Koushiappas , Bruno Alexandre , João Magueijo

While gravitational lens inversion holds great promise to reveal the structure of the light-deflecting mass distribution, both light and dark, the existence of various kinds of degeneracies implies that care must be taken when interpreting…

Astrophysics of Galaxies · Physics 2024-02-28 Jori Liesenborgs , Derek Perera , Liliya L. R. Williams

Assessing the probability that two or more gravitational waves (GWs) are lensed images of the same source requires an understanding of the image properties, including their relative phase shifts in strong lensing (SL). For non-precessing,…

General Relativity and Quantum Cosmology · Physics 2021-03-31 Jose María Ezquiaga , Daniel E. Holz , Wayne Hu , Macarena Lagos , Robert M. Wald

Gravitational lensing has emerged as a powerful probe of the matter distribution on subgalactic scales, which itself may contain important clues about the fundamental origins and properties of dark matter. Broadly speaking, two different…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-29 Francis-Yan Cyr-Racine , Charles R. Keeton , Leonidas A. Moustakas

We examine general physical parameterisations for viable gravitational models in the $f(R)$ framework. This is related to the mass of an additional scalar field, called the scalaron, that is introduced by the theories. Using a simple…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Shaun A. Thomas , Stephen A. Appleby , Jochen Weller

This paper shows that the mass-sheet degeneracy and other degeneracies in lensing have simple geometrical interpretations: they are mostly rescalings of the arrival-time surface. Different degeneracies appear in Local Group lensing and in…

Astrophysics · Physics 2009-10-31 Prasenjit Saha

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

In this paper, we study the gravitational lensing around the static and spherically symmetric DD black holes, which we recently derived as perturbations of the Schwarzschild geometry within the revised Deser-Woodard theory of nonlocal…

General Relativity and Quantum Cosmology · Physics 2026-04-16 Rocco D'Agostino , Vittorio De Falco

Dark matter currents in the large-scale structure give rise to gravitomagnetic terms in the metric, which affect the light propagation. Corrections to the weak lensing power spectrum due to these gravitomagnetic potentials are evaluated by…

Astrophysics · Physics 2013-03-07 Bjoern Malte Schaefer , Matthias Bartelmann

We study weak gravitational lensing by the cosmic large-scale structure of the 21-cm radiation background in the 3d-weak lensing formalism. The interplay between source distance measured at finite resolution, visibility and lensing terms is…

Cosmology and Nongalactic Astrophysics · Physics 2022-05-10 Jose Agustin Lozano Torres , Bjoern Malte Schaefer

We describe a new method to parameterise dark energy theories including massive gravity, elastic dark energy and tensor-metric theories. We first examine a framework to describe any second order Lagrangian which depends on the variation of…

General Relativity and Quantum Cosmology · Physics 2018-12-26 James Edholm , Jonathan Pearson

Just like light, gravitational waves (GWs) are deflected and magnified by gravitational fields as they propagate through the Universe. However, their low frequency, phase coherence and feeble coupling to matter allow for distinct lensing…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-29 Giovanni Tambalo , Miguel Zumalacárregui , Liang Dai , Mark Ho-Yeuk Cheung

In this study, we investigate gravitational lensing within modified gravity frameworks, focusing on the Hu-Sawicki $f(R)$ and normal branch Dvali-Gabadadze-Porrati (nDGP) models, and we compare these results with those obtained from general…

General Relativity and Quantum Cosmology · Physics 2025-01-03 Ali Tizfahm , Saeed Fakhry , Javad T. Firouzjaee , Antonino Del Popolo

This paper reviews statistical methods recently developed to reconstruct and analyze dark matter mass maps from weak lensing observations. The field of weak lensing is motivated by the observations made in the last decades showing that the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 S. Pires , J. -L. Starck , A. Refregier

Future weak lensing surveys will map the evolution of matter perturbations and gravitational potentials, yielding a new test of general relativity on cosmic scales. They will probe the relations between matter overdensities, local…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-15 Gong-Bo Zhao , Levon Pogosian , Alessandra Silvestri , Joel Zylberberg

Our modified gravity theory (MOG) was used successfully in the past to explain a range of astronomical and cosmological observations, including galaxy rotation curves, the CMB acoustic peaks, and the galaxy mass power spectrum. MOG was also…

Astrophysics · Physics 2011-09-28 J. W. Moffat , V. T. Toth

The accelerated expansion of the Universe remains one of the central open problems in modern cosmology. While the $\Lambda$CDM model successfully describes a wide range of observations, the physical nature of dark energy is still unknown,…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-08 Leandro Pardo , Leonardo Castañeda

Underlying cosmologies with deceleration parameter, $q_0=-0.51^{+0.03}_{-0.24},$ may be interpreted as having $q_0=-0.55,$ on the basis of weak gravitational lensing effects.

Astrophysics · Physics 2007-05-23 Andrew J. Barber
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