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Related papers: Gravitational Lensing Effects in the LTB Model

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Concepts developed in the gravitational lensing techniques such as shear, convergence, tangential and radial arcs maybe used to see how tenable inhomogeneous models proposed to explain the acceleration of the universe models are. We study…

Cosmology and Nongalactic Astrophysics · Physics 2009-05-09 Sima Ghassemi , Salomeh Khoeini Moghaddam , Reza Mansouri

Gravity waves (GW) in the early universe generate B-type polarization in the cosmic microwave background (CMB), which can be used as a direct way to measure the energy scale of inflation. Gravitational lensing contaminates the GW signal by…

Astrophysics · Physics 2008-11-26 Uros Seljak , Christopher M. Hirata

Extending the Kaiser-Stebbins mechanism we propose here a method for detecting relics of topological defects such as cosmic strings based on lens-induced small-scale B-type polarization in the CMB. Models of inflation, in which large scale…

Astrophysics · Physics 2009-10-31 K. Benabed , F. Bernardeau

Weak gravitational lensing by intervening large-scale structure induces a distinct signature in the cosmic microwave background (CMB) that can be used to reconstruct the weak-lensing displacement map. Estimators for individual Fourier modes…

Astrophysics · Physics 2016-08-30 Michael Kesden , Asantha Cooray , Marc Kamionkowski

CMB anisotropies are modified by the weak lensing effect of intervening large scale structures on the photon path from the last scattering surface to the observer. This has to be accounted for when observational data of sensitive…

Astrophysics · Physics 2010-10-27 Jonathan Rocher , Karim Benabed , Francois Bouchet

The local void model has lately attracted considerable attention since it can explain the present apparent accelerated expansion of the universe without introducing dark energy. However, in order to justify this model as an alternative…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-13 Keiki Saito , Akihiro Ishibashi , Hideo Kodama

We provide a detailed treatment and comparison of the weak lensing effects due to large-scale structure (LSS), or scalar density perturbations and those due to gravitational waves(GW) or tensor perturbations, on the temperature and…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Hamsa Padmanabhan , Aditya Rotti , Tarun Souradeep

Hu [Phys. Rev. D62 (2000) 043007] has presented a harmonic-space method for calculating the effects of weak gravitational lensing on the cosmic microwave background (CMB) over the full sky. Computing the lensed power spectra to first order…

Astrophysics · Physics 2009-11-07 Anthony Challinor , Gayoung Chon

Weak lensing of the CMB changes the unlensed temperature anisotropy and polarization power spectra. Accounting for the lensing effect will be crucial to obtain accurate parameter constraints from sensitive CMB observations. Methods for…

Astrophysics · Physics 2009-11-10 Anthony Challinor , Antony Lewis

The weak lensing effect on the cosmic microwave background (CMB) induces distortions in spatial pattern of CMB anisotropies, and statistical properties of CMB anisotropies become a weakly non-Gaussian field. We first summarize the weak…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-17 Toshiya Namikawa

Cosmological inhomogeneities gravitationally deflect radiation propagating from distant sources, transforming the spatial and angular correlation functions of intrinsic source properties. For a gaussian distribution of deflections (e.g.…

Astrophysics · Physics 2007-05-23 Eric V. Linder

We present a simple gravitational lens model to illustrate the ease of using the embedded lensing theory when studying cosmic voids. It confirms the previously used repulsive lensing models for deep voids. We start by estimating magnitude…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-17 Bin Chen , Ronald Kantowski , Xinyu Dai

We investigate the weak gravitational lensing effect due to the large-scale structure of the universe on two-point correlations of local maxima ({\em hotspots}) in the 2D sky map of the cosmic microwave background (CMB) anisotropy.…

Astrophysics · Physics 2016-08-30 Masahiro Takada , Eiichiro Komatsu , Toshifumi Futamase

We summarize the physical mechanism by which the Cosmic Microwave Background acquires a small degree of polarization. We discuss the imprint left by gravitational waves and the use of polarization as a test of the inflationary paradigm. We…

Astrophysics · Physics 2007-05-23 Matias Zaldarriaga

When a cosmic microwave background (CMB) photon travels from the surface of last scatter through spacetime metric perturbations, the polarization vector may rotate about its direction of propagation. This gravitational rotation is distinct…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-31 Liang Dai

We investigate the weak lensing corrections to the CMB polarization anisotropies. We concentrate on the effect of rotation and show that the rotation of polarisation is a true physical effect which has to be taken into account at second…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-25 Enea Di Dio , Ruth Durrer , Giuseppe Fanizza , Giovanni Marozzi

One of the most promising ways of detecting primordial gravitational waves generated during inflation is to observe B-modes of polarization, generated by Thomson scattering after reionization, in the cosmic microwave background (CMB). Large…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Scott Dodelson

Impacts of observational systematic errors on the lensing analysis of the cosmic microwave background (CMB) polarization are investigated by numerical simulations. We model errors of gain, angle, and pointing in observation of the CMB…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-10 Ryo Nagata , Toshiya Namikawa