Results 11 to 20 of about 121 (117)
Weak gravitational lensing by voids [PDF]
Monthly Notices of the Royal Astronomical Society, 1999 We consider the prospects for detecting weak gravitational lensing by underdensities (voids) in the large-scale matter distribution. We derive the basic expressions for magnification and distortion by spherical voids. Clustering of the background sources and cosmic variance are the main factors which limit in principle the detection of lensing by voids.
Amendola, Luca +2 more
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Weak gravitational lensing of the CMB [PDF]
Physics Reports, 2006 Weak gravitational lensing has several important effects on the cosmic microwave background (CMB): it changes the CMB power spectra, induces non-Gaussianities, and generates a B-mode polarization signal that is an important source of confusion for the signal from primordial gravitational waves.
Lewis, Antony, Challinor, Anthony
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Weak Gravitational Lensing of Finite Beams [PDF]
Physical Review Letters, 2017 The standard theory of weak gravitational lensing relies on the infinitesimal light beam approximation. In this context, images are distorted by convergence and shear, the respective sources of which unphysically depend on the resolution of the distribution of matter---the so-called Ricci-Weyl problem.
Fleury, Pierre +2 more
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Weak gravitational lensing by dark clusters [PDF]
Monthly Notices of the Royal Astronomical Society, 2002 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 optical clusters. However, a significant fraction are nonvirialized overdensities still in the process of gravitational ...
Weinberg, Nevin N., Kamionkowski, Marc
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Nulling tomography with weak gravitational lensing [PDF]
Physical Review D, 2005 We explore several strategies of eliminating (or nulling) the small-scale information in weak lensing convergence power spectrum measurements in order to protect against undesirable effects, for example the effects of baryonic cooling and pressure forces on the distribution of large-scale structures. We selectively throw out the small-scale information
Huterer, Dragan, White, Martin
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, 2020 In this presentation I review cosmological measurements with weak gravitational lensing using the cosmic shear technique. An intriguing tension in the parameter S8=sigma8*sqrt(Omega_m/0.3) between low-z large-scale-structure probes and the Planck primary CMB probes has been observed. This is reminiscent of the well-known H0 tension, albeit currently at
Daniel Gruen +2 more
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Scholarpedia, 2017 Invited and refereed contribution to ...
Matthias Bartelmann, Matteo Maturi
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Light on dark matter with weak gravitational lensing [PDF]
IEEE Signal Processing Magazine, 2010 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 visible matter represents only about 4-5% of the Universe, the rest being dark.
Sandrine Pires +2 more
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Weak Gravitational Lensing [PDF]
Proceedings of Frontiers of Fundamental Physics 14 — PoS(FFP14), 2008 In this brief review I consider the advances made in weak gravitational lensing over the last 8 years, concentrating on the large scales - cosmic shear. I outline the theoretical developments, observational status, and the challenges which cosmic shear must overcome to realise its full potential. Finally I consider the prospects for probing Dark Energy
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Circular Orbit of a Particle and Weak Gravitational Lensing [PDF]
Physical Review D, 2020 The purpose of this paper is twofold. First, we introduce a geometric approach to study the circular orbit of a particle in static and spherically symmetric spacetime based on Jacobi metric. Second, we apply the circular orbit to study the weak gravitational deflection of null and time-like particles based on Gauss-Bonnet theorem.
Zonghai Li, Guodong Zhang, Ali Övgün
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