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Related papers: Dark energy and CMB bispectrum

200 papers

We investigate the possibility of constraining Chaplygin dark energy models with current Integrated Sachs Wolfe effect data. In the case of a flat universe we found that generalized Chaplygin gas models must have an energy density such that…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Tommaso Giannantonio , Alessandro Melchiorri

Forthcoming CMB experiments will allow us to accurately investigate the power spectrum at very small scales ($\ell > 1000$). We predict the level of the primary anisotropies, given the actual CMB measurements. The secondary anisotropies…

Astrophysics · Physics 2009-11-07 N. Aghanim , P. G. Castro , A. Melchiorri , J. Silk

A primary goal for cosmology and particle physics over the coming decade will be to unravel the nature of the dark energy that drives the accelerated expansion of the Universe. In particular, determination of the equation-of-state of dark…

Astrophysics · Physics 2011-05-12 Joshua A. Frieman , Dragan Huterer , Eric V. Linder , Michael S. Turner

Dark matter and dark energy are usually assumed to couple only gravitationally. An extension to this picture is to model dark energy as a scalar field coupled directly to cold dark matter. This coupling leads to new physical effects, such…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Francesco Pace , Marco Baldi , Lauro Moscardini , David Bacon , Robert Crittenden

We explore the possibility of using the B-type polarization of the CMB to map the large-scale structures of the Universe taking advantage of the lens effects on the CMB polarization. The functional relation between the B component with the…

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

Cosmological models with variable and modified equations of state for dark energy are confronted with observational data, including Type Ia supernovae, Hubble parameter data $H(z)$ from different sources, and observational manifestations of…

General Relativity and Quantum Cosmology · Physics 2022-03-29 German S. Sharov , Vasily E. Myachin

The cross-correlation between cosmic microwave background (CMB) temperature anisotropies and the large scale structure (LSS) traced by the galaxy distribution, or sources at different wavelengths, is now well known. This correlation results…

Astrophysics · Physics 2009-11-13 Asantha Cooray , Alessandro Melchiorri

Weak lensing of galaxies by large scale structure can potentially measure cosmological quantities as accurately as the cosmic microwave background (CMB). However, the relation between observables and fundamental parameters is more complex…

Astrophysics · Physics 2009-10-31 Wayne Hu , Max Tegmark

Lensing of the CMB generates a significant bispectrum, which should be detected by the Planck satellite at the 5-sigma level and is potentially a non-negligible source of bias for f_NL estimators of local non-Gaussianity. We extend current…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Antony Lewis , Anthony Challinor , Duncan Hanson

Supernova evidence for a negative-pressure dark energy (e.g., cosmological constant or quintessence) that contributes a fraction $\Omega_\Lambda\simeq0.7$ of closure density has been bolstered by the discrepancy between the total density,…

Astrophysics · Physics 2007-05-23 Marc Kamionkowski , Ari Buchalter

The immediate observational consequence of a non-trivial spatial topology of the Universe is that an observer could potentially detect multiple images of radiating sources. In particular, a non-trivial topology will generate pairs of…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-23 S. D. P. Vitenti , M. P. Lima , M. J. Reboucas

The anisotropies in the cosmic microwave background (CMB) provide our best laboratory for testing models of the formation and evolution of large-scale structure. The rich features in the cosmic microwave background anisotropy spectrum, in…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Zhen Pan , Lloyd Knox , Martin White

Recent studies by a number of independent collaborations, have correlated the CMB temperatures measured by the WMAP satellite with different galaxy surveys that trace the matter distribution with light from the whole range of the…

Astrophysics · Physics 2009-11-10 E. Gaztanaga , M. Manera , T. Multamaki

Extensions to the $\Lambda\textrm{CDM}$ model prior to recombination can modify the growth of perturbations around radiation-matter equality, leaving a distinct signature in the matter power spectrum. Upcoming large-scale structure surveys…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-09 Raphaël Kou , Antony Lewis

We examine the cosmic microwave background (CMB) anisotropy for signatures of early quintessence dark energy -- a non-negligible quintessence energy density during the recombination and structure formation eras. Only very recently does the…

If the dark energy equation of state is anisotropic, the expansion rate of the universe becomes direction-dependent at late times. We show that such models are not only cosmologically viable but that they could explain some of the observed…

Astrophysics · Physics 2010-11-11 Tomi Koivisto , David F. Mota

We present the first detection of a correlation between the Lyman-$\alpha$ forest and cosmic microwave background (CMB) lensing. For each Lyman-$\alpha$ forest in SDSS-III/BOSS DR12, we correlate the one-dimensional power spectrum with the…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-15 Cyrille Doux , Emmanuel Schaan , Eric Aubourg , Ken Ganga , Khee-Gan Lee , David N. Spergel , Julien Tréguer

Matter inhomogeneities along the line of sight deflect the cosmic microwave background (CMB) photons originating at the last scattering surface at redshift $z \sim 1100$. These distortions modify the pattern of CMB polarization. We identify…

Astrophysics · Physics 2009-10-31 Jacek Guzik , Uros Seljak , Matias Zaldarriaga

A hypothetical dark energy component may have an equation of state that is different from a cosmological constant and possibly even changing in time. The spacing of the cosmic microwave background peaks is sensitive to the ratio of the…

Astrophysics · Physics 2007-05-23 Michael Doran , Matthew Lilley , Jan Schwindt , Christof Wetterich

In this paper we present a power spectrum formalism that combines the full three-dimensional information from the galaxy ellipticity field, with information from the cosmic microwave background (CMB). We include in this approach galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 T. D. Kitching , A. F. Heavens , S. Das