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There is currently a discrepancy in the measured value of the amplitude of matter clustering, parameterised using $\sigma_8$, inferred from galaxy weak lensing, and cosmic microwave background data, which could be an indication of new…

Cosmology and Nongalactic Astrophysics · Physics 2019-04-15 Thomas D. Kitching , Licia Verde , Alan F. Heavens , Raul Jimenez

We present a Markov-Chain Monte-Carlo (MCMC) forecast for the precision of neutrino mass and cosmological parameter measurements with a Euclid-like galaxy clustering survey. We use a complete perturbation theory model for the galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-28 Anton Chudaykin , Mikhail M. Ivanov

The weak gravitational lensing effect, small coherent distortions of galaxy images by means of a gravitational tidal field, can be used to study the relation between the matter and galaxy distribution. In this context, weak lensing has so…

Astrophysics · Physics 2014-11-18 P. Simon , P. Watts , P. Schneider , H. Hoekstra , M. D. Gladders , H. K. C. Yee , B. C. Hsieh , H. Lin

It is usually assumed that the ellipticity power spectrum measured in weak lensing observations can be expressed as an integral over the underlying matter power spectrum. This is true at second order in the gravitational potential. We…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Elisabeth Krause , Christopher M. Hirata

Weak gravitational lensing is one of the key probes of the cosmological model, dark energy, and dark matter, providing insight into both the cosmic expansion history and large scale structure growth history. Taking into account a broad…

Cosmology and Nongalactic Astrophysics · Physics 2012-11-12 Sudeep Das , Roland de Putter , Eric V. Linder , Reiko Nakajima

With the availability of galaxy distance indicators in weak lensing surveys, lensing tomography can be harnessed to constrain the three-dimensional (3D) matter power spectrum over a range of redshift and physical scale. By combining…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Patrick Simon

We compute the spherical-sky weak-lensing power spectrum of the shear and convergence. We discuss various approximations, such as flat-sky, and first- and second- order Limber equations for the projection. We find that the impact of…

General relativistic corrections to the galaxy power spectrum appearing at the horizon scale, if neglected, may induce biases on the measured values of the cosmological parameters. In this paper, we study the impact of general relativistic…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 L. Lopez-Honorez , O. Mena , S. Rigolin

We study cosmic magnification beyond lensing in a late-time universe dominated by quintessence and cold dark matter. The cosmic magnification angular power spectrum, especially going beyond the well-known lensing effect, provides an…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-20 Enas Mohamed , Didam Duniya , Hassan Abdalla , Bishop Mongwane

We consider cosmological models in which dark matter feels a fifth force mediated by the dark energy scalar field, also known as coupled dark energy. Our interest resides in estimating forecasts for future surveys like Euclid when we take…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-02 Santiago Casas , Luca Amendola , Marco Baldi , Valeria Pettorino , Adrian Vollmer

Upcoming photometric lensing surveys will considerably tighten constraints on the neutrino mass and the dark energy equation of state. Nevertheless it remains an open question of how to optimally extract the information and how well the…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-12 Peter L. Taylor , Thomas D. Kitching , Jason D. McEwen

We study the lensing convergence power spectrum and its covariance for a standard LCDM cosmology. We run 400 cosmological N-body simulations and use the outputs to perform a total of 1000 independent ray-tracing simulations. We compare the…

Cosmology and Nongalactic Astrophysics · Physics 2012-03-12 Masanori Sato , Takashi Hamana , Ryuichi Takahashi , Masahiro Takada , Naoki Yoshida , Takahiko Matsubara , Naoshi Sugiyama

We report a detection of the coherent distortion of faint galaxies arising from gravitational lensing by foreground structures. This ``cosmic shear'' is potentially the most direct measure of the mass power spectrum, as it is unaffected by…

Astrophysics · Physics 2011-05-05 David Bacon , Alexandre Refregier , Richard Ellis

In the era of precision cosmology, establishing the correct magnitude of statistical errors in cosmological parameters is of crucial importance. However, widely used approximations in galaxy surveys analyses can lead to parameter…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-07 Nicola Bellomo , José Luis Bernal , Giulio Scelfo , Alvise Raccanelli , Licia Verde

Any theory invoked to explain cosmic acceleration predicts consistency relations between the expansion history, structure growth, and all related observables. Currently there exist high-quality measurements of the expansion history from…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 R. Ali Vanderveld , Michael J. Mortonson , Wayne Hu , Tim Eifler

In recent years cosmic shear, the weak gravitational lensing effect by the large-scale structure of the Universe, has proven to be one of the observational pillars on which the cosmological concordance model is founded. Several cosmic shear…

Astrophysics · Physics 2008-03-12 B. Joachimi , P. Schneider , T. Eifler

We present new results on the gravitational lensing shear and magnification power spectra obtained from numerical simulations of a flat cosmology with a cosmological constant. These results are of considerable interest since both the shear…

Astrophysics · Physics 2009-11-07 Andrew J. Barber , A. N. Taylor

The results from weak gravitational lensing analyses are subject to a cosmic variance error term that has previously been estimated assuming Gaussian statistics. In this letter we address the issue of estimating cosmic variance errors for…

Weak gravitational lensing is a powerful tool for studying both the geometry and the dynamics of the Universe. Its power spectrum contains information on the sources emitting photons and on the large--scale structures that these hotons…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-02 Stefano Camera , Daniele Bertacca , Antonaldo Diaferio , Nicola Bartolo , Sabino Matarrese

In the search for the nature of dark energy most cosmological probes measure simple functions of the expansion rate. While powerful, these all involve roughly the same dependence on the dark energy equation of state parameters, with…

Astrophysics · Physics 2009-11-10 Eric V. Linder