Results 31 to 40 of about 49,349 (281)

Effects of early dark energy on strong cluster lensing [PDF]

, 2006
We use the semi-analytic method developed by Fedeli et al. for computing strong-lensing optical depths to study the statistics of gravitational arcs in four dark-energy cosmologies. Specifically, we focus on models with early dark energy and compare them
Bartelmann, Bartelmann, Bartelmann, Bartelmann, Bartelmann, Benson, Bond, Brax, C. Fedeli, Caldwell, Cassano, Chandrasekhar, Dalal, Dolag, Doran, Doran, Fedeli, Ferreira, Gladders, Goldstein, Hasinger, Hawkins, Keeton, Lacey, Li, M. Bartelmann, Manera, Maor, Meneghetti, Meneghetti, Meneghetti, Meneghetti, Mota, Navarro, Navarro, Peebles, Peebles, Press, Randall, Readhead, Rebolo, Riess, Smail, Somerville, Spergel, Tegmark, Thompson, Torri, Wambsganss, Wang, Wetterich, Wetterich, Zaritsky   +52 more
core   +1 more source

Evolving Morphology of Resolved Stellar Einstein Rings

The Astrophysical Journal, 2023
We consider strong gravitational lensing by nearby stars. Using our wave-optical treatment of lensing phenomena, we study Einstein rings that may form around nearby stellar lenses.
Slava G. Turyshev, Viktor T. Toth
doaj   +1 more source

GRAVITATIONAL LENSING EFFECT ON COSMIC MICROWAVE BACKGROUND ANISOTROPIES: A POWER SPECTRUM APPROACH [PDF]

, 1995
The effect of gravitational lensing on cosmic microwave background (CMB) anisotropies is investigated using the power spectrum approach. The lensing effect can be calculated in any cosmological model by specifying the evolution of gravitational potential.
Seljak, Uros
core   +2 more sources

Gravitational lensing and modified Newtonian dynamics [PDF]

, 2001
Gravitational lensing is most often used as a tool to investigate the distribution of (dark) matter in the universe, but, if the mass distribution is known a priori, it becomes, at least in principle, a powerful probe of gravity itself.
Daniel J. Mortlock, Edwin L. Turner, Tadros, Qin   +3 more
core   +8 more sources

Shadow and Weak Deflection Angle of a Black Hole in Nonlocal Gravity

Universe, 2022
Black hole shadow and gravitational lensing play important roles in testing gravitational theories in the strong field regime. As the first-order modifications from quantum gravity, the nonlocality can be manifested by black hole shadow and gravitational
Qi-Ming Fu, Shao-Wen Wei, Li Zhao, Yu-Xiao Liu, Xin Zhang   +4 more
doaj   +1 more source

Strong Deflection Gravitational Lensing for the Photons Coupled to the Weyl Tensor in a Conformal Gravity Black Hole

Universe, 2023
In the present paper, strong deflection gravitational lensing is studied in a conformal gravity black hole. With the help of geometric optics limits, we have formulated the light cone conditions for the photons coupled to the Weyl tensor in a conformal ...
Ghulam Abbas, Ali Övgün, Asif Mahmood, Muhammad Zubair   +3 more
doaj   +1 more source

Einstein beams and the diffractive aspect of gravitationally-lensed light

New Journal of Physics, 2023
The study of light lensed by cosmic matter has yielded much information about astrophysical questions. Observations are explained using geometrical optics following a ray-based description of light.
V Rodríguez-Fajardo, T P Nguyen, K S Hocek, J M Freedman, E J Galvez   +4 more
doaj   +1 more source

Editorial of Modified Theories of Gravity and Cosmological Applications

Universe, 2022
General Relativity is a theory of gravity that describes some of the effects of gravity with high accuracy, such as solar system tests, gravitational lensing, gravitational waves, black holes, deflection angle, etc [...]
Panayiotis Stavrinos, Emmanuel Saridakis
doaj   +1 more source

Relationship between High-Energy Absorption Cross Section and Strong Gravitational Lensing for Black Hole

, 2011
In this paper, we obtain a relation between the high-energy absorption cross section and the strong gravitational lensing for a static and spherically symmetric black hole. It provides us a possible way to measure the high-energy absorption cross section
A. A. Starobinsky, C. W. Misner, Heng Guo, K. S. Virbhadra, Shao-Wen Wei, Yu-Xiao Liu   +5 more
core   +1 more source

CLASS B2108+213: A new wide separation gravitational lens system [PDF]

, 2004
We present observations of CLASS B2108+213, the widest separation gravitational lens system discovered by the Cosmic Lens All-Sky Survey. Radio imaging using the VLA at 8.46 GHz and MERLIN at 5 GHz shows two compact components separated by 4.56 arcsec ...
Biggs, A. D., Blandford, R. D., Browne, I. W. A., de Bruyn, A. G., Fassnacht, C. D., Jackson, N. J., Koopmans, L. V. E., Mao, S., McKean, J. P., Myers, S. T., Norbury, M. A., Pearson, T. J., Phillips, P. M., Readhead, A. C. S., Rusin, D., Treu, T., Wilkinson, P. N., York, T. D.   +17 more
core   +4 more sources