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Related papers: Gravitational Microlensing by the Ellis Wormhole

200 papers

We investigate the predictions of Einsteinian Cubic Gravity (ECG) for the lensing effects due to supermassive black holes at the center of Milky Way and other galaxies. Working in the context of spherical symmetry, we obtain the metric…

General Relativity and Quantum Cosmology · Physics 2019-02-01 Mohammad Bagher Jahani Poshteh , Robert B. Mann

Foundations of standard theory of microlensing are described, namely we consider microlensing stars in Galactic bulge, the Magellanic Clouds or other nearby galaxies. We suppose that gravitational microlenses lie between an Earth observer…

Astrophysics · Physics 2017-08-23 Alexander F. Zakharov

We investigate the strong deflection limit of gravitational lensing by a Schwarzschild black hole embedded in an external gravitational field. The study of this model, analogous to the Chang & Refsdal lens in the weak deflection limit, is…

General Relativity and Quantum Cosmology · Physics 2009-11-11 V. Bozza , M. Sereno

We employ VLTI GRAVITY to resolve, for the first time, the two images generated by a gravitational microlens. The measurements of the image separation \theta_{-,+}=3.78 +/- 0.05 mas, and hence the Einstein radius \theta_E =1.87 +/- 0.03…

If the Galaxy contains ~10^{11}M_sol in cold gas clouds of ~Jovian mass and \~AU size, these clouds will act as converging lenses for optical light, magnifying background stars at a detectable rate. The resulting light curves can resemble…

Astrophysics · Physics 2009-10-30 B. T. Draine

Foundations of standard theory of microlensing are described, namely we consider microlensing stars in Galactic bulge, the Magellanic Clouds or other nearby galaxies. We suppose that gravitational microlenses lie between an Earth observer…

Astrophysics · Physics 2007-05-23 A. F. Zakharov

We study the linear polarization from the accretion disk around a class of static traversable wormholes. Applying the simplified model of a magnetized fluid ring orbiting in the equatorial plane, we search for characteristic signatures,…

General Relativity and Quantum Cosmology · Physics 2022-06-22 Valentin Delijski , Galin Gyulchev , Petya Nedkova , Stoytcho Yazadjiev

It has been shown by Paczy\'nski that gravitational microlensing is potentially a useful method for detecting the dark constituents of the halo of our galaxy, if their mass lies in the approximate domain $10^{-6}<M/M_\odot<10^{-1}$.…

Astrophysics · Physics 2008-02-03 Philippe Jetzer

Unlike the electromagnetic radiation from astrophysical objects, gravitational waves (GWs) from binary star mergers have much longer wavelengths and are coherent. For ground-based GW detectors, when the lens object between the source and…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-05 Kai Liao , Shuxun Tian , Xuheng Ding

Gravitational lensing causes background galaxy images to become aligned, and the statistical characteristics of the image alignments can then be used to constrain the power spectrum of mass fluctuations. Analyses of gravitational lensing…

Astrophysics · Physics 2017-08-23 A. F. Heavens

We describe the feasibility of detecting the gravitational deflection of light emitted by stars moving under the influence of the massive object at the Galactic center. Light emitted by a star orbiting behind the central mass has a smaller…

Astrophysics · Physics 2009-11-10 Adi Nusser , Tom Broadhurst

It is well known that general relativity is an effective theory of gravity at low energy scale, and actually quantum effects cannot be ignored in the strong-field regime. As a strong gravitational object, black hole plays a key role in…

General Relativity and Quantum Cosmology · Physics 2022-03-23 Qi-Ming Fu , Xin Zhang

Weak gravitational lensing is a unique probe of the dark side of the universe: it provides a direct way to map the distribution of dark matter around galaxies, clusters of galaxies and on cosmological scales. Furthermore, the measurement of…

Astrophysics · Physics 2010-01-07 Henk Hoekstra , Bhuvnesh Jain

An overview is given on those theoretical gravitational lensing results that can be formulated in a spacetime setting, without assuming that the gravitational fields are weak and that the bending angles are small. The first part is devoted…

General Relativity and Quantum Cosmology · Physics 2016-11-15 Volker Perlick

We present the analysis of the light curves of 8.5 million stars observed during two seasons by EROS (Experience de Recherche d'Objets Sombres), in the galactic plane away from the bulge. Three stars have been found that exhibit luminosity…

Astrophysics · Physics 2008-11-26 F. Derue , C. Afonso , C. Alard , J-N. Albert

We study strong gravitational lensing by a class of static wormhole geometries. Analytical approaches to the same are developed, and the results differ substantially from strong lensing by black holes, first reported by Bozza. We consider…

General Relativity and Quantum Cosmology · Physics 2023-11-07 Rajibul Shaikh , Pritam Banerjee , Suvankar Paul , Tapobrata Sarkar

We report the ALMA Band 7 observations of 86 Herschel sources that likely contain gravitationally-lensed galaxies. These sources are selected with relatively faint 500 $\mu$m flux densities between 15 to 85 mJy in an effort to characterize…

We propose gravitational microlensing as a way of testing the emergent gravity theory recently proposed by Eric Verlinde~\cite{Verlinde:2016toy}. We consider two limiting cases: the dark mass of maximally anisotropic pressures (Case I) and…

General Relativity and Quantum Cosmology · Physics 2017-04-05 Lei-Hua Liu , Tomislav Prokopec

Recently, two of us have found numerically rotating Ellis wormholes as solutions of 4-dimensional Einstein gravity coupled to a phantom field. In this paper, we investigate possible observational signatures to identify similar objects in…

General Relativity and Quantum Cosmology · Physics 2016-07-19 Menglei Zhou , Alejandro Cardenas-Avendano , Cosimo Bambi , Burkhard Kleihaus , Jutta Kunz

We calculate the abundance of dark-matter concentrations that are sufficiently overdense to produce a detectable weak-gravitational-lensing signal. Most of these overdensities are virialized halos containing identifiable X-ray and/or…

Astrophysics · Physics 2009-11-07 Nevin N. Weinberg , Marc Kamionkowski
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