Results 21 to 30 of about 1,064,480 (240)
Constraints on early dark energy from CMB lensing and weak lensing tomography [PDF]
. We estimate the B-polarisation induced in the Cosmic Microwave Background by the non-linear evolution of density perturbations. Using the second-order Boltzmann code SONG, our analysis incorporates, for the first time, all physical effects at ...
Schafer, B. +3 more
core +3 more sources
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
openaire +3 more sources
Invited and refereed contribution to ...
Matthias Bartelmann, Matteo Maturi
openaire +2 more sources
Light on dark matter with weak gravitational lensing [PDF]
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
openaire +3 more sources
Circular Orbit of a Particle and Weak Gravitational Lensing [PDF]
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
openaire +4 more sources
Gravitational Lensing and Optical Geometry [PDF]
The year 2019 saw the centenary of Eddington's eclipse expeditions and the corroboration of Einstein's general relativity by gravitational lensing. To mark the occasion, a Special Issue of Universe has been dedicated to the theoretical aspects of strong ...
core +1 more source
Weak gravitational lensing by stringy black holes [PDF]
In this paper, we discuss the weak gravitational lensing in the context of stringy black holes. Initially, we examine the deflection angle of photon by charged stringy black hole. For this desire, we compute the Gaussian optical curvature and implement the Gauss-Bonnet theorem to investigate the deflection angle for spherically balanced spacetime of ...
Wajiha Javed +3 more
openaire +4 more sources
Time delay of photons coupled to Weyl tensor in a regular phantom black hole
Time delay of the photons coupled to the Weyl tensor in a regular phantom black hole is investigated in both weak and strong deflection gravitational lensing. We find that the time delay in the weak deflection lensing strongly depends on the phantom hair
Xu Lu, Yi Xie
doaj +1 more source
Simulations of weak gravitational lensing [PDF]
15 pages, 9 figures, Astroparticle Physics in ...
White, Martin, Vale, Chris
openaire +2 more sources
Optimizing tomography for weak gravitational lensing surveys [PDF]
ABSTRACT The subject of this paper is optimization of weak lensing tomography: we carry out numerical minimization of a measure of total statistical error as a function of the redshifts of the tomographic bin edges by means of a Nelder–Mead algorithm in order to optimize the sensitivity of weak lensing with respect to different ...
Marvin Sipp +2 more
openaire +2 more sources

