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We study the signature of primordial non-Gaussianity imprinted on the power spectrum of the 21-cm line differential brightness temperature during dark ages. Employing the perturbative treatment of gravitational clustering, we quantitatively…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-24 Daisuke Yamauchi

We study how well the Gaussian approximation is valid for computing the covariance matrices of the convergence power and bispectrum in weak gravitational lensing analyses. We focus on its impact on the cosmological parameter estimations by…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Masanori Sato , Takahiro Nishimichi

We investigate the effects of non-Gaussianity in the primordial density field on the reionization history. We rely on a semi-analytic method to describe the processes acting on the intergalactic medium (IGM), relating the distribution of…

Astrophysics · Physics 2010-03-26 D. Crociani , L. Moscardini , M. Viel , S. Matarrese

A measurement of primordial non-gaussianity will be of paramount importance to distinguish between different models of inflation. Cosmic microwave background (CMB) anisotropy observations have set unprecedented bounds on the non-gaussianity…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-14 Julian B. Muñoz , Yacine Ali-Haïmoud , Marc Kamionkowski

The measurement of large scale anisotropies in cosmic ray arrival directions at energies above 10^13 eV is performed through the detection of Extensive Air Showers produced by cosmic ray interactions in the atmosphere. The observed…

Instrumentation and Methods for Astrophysics · Physics 2011-08-31 R. Bonino , V. V. Alekseenko , O. Deligny , P. L. Ghia , M. Grigat , A. Letessier-Selvon , H. Lyberis , S. Mollerach , S. Over , E. Roulet

A detection of the level of non-Gaussianity in the CMB data is essential to discriminate among inflationary models and also to test alternative primordial scenarios. However, the extraction of primordial non-Gaussianity is a difficult…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-07 A. Bernui , M. J. Reboucas , A. F. F. Teixeira

Nonlinear objects like halos and voids exhibit a scale-dependent bias on linear scales in massive neutrino cosmologies. The shape of this scale-dependent bias is a unique signature of the neutrino masses, but the amplitude of the signal is…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-01 Arka Banerjee , Emanuele Castorina , Francisco Villaescusa-Navarro , Travis Court , Matteo Viel

A detection or nondetection of primordial non-Gaussianity in the CMB data is essential not only to test alternative models of the physics of the early universe but also to discriminate among classes of inflationary models. Given this far…

Cosmology and Nongalactic Astrophysics · Physics 2010-09-15 A. Bernui , M. J. Reboucas

Many inflation models predict that primordial density perturbations have a nonzero three-point correlation function, or bispectrum in Fourier space. Of the several possibilities for this bispectrum, the most commmon is the local-model…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-01 Razieh Emami , Emanuela Dimastrogiovanni , Jens Chluba , Marc Kamionkowski

The forthcoming generation of wide-field galaxy surveys will probe larger volumes and galaxy densities, thus allowing for a much larger signal-to-noise ratio for higher-order clustering statistics, in particular the galaxy bispectrum.…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-15 Azadeh Moradinezhad Dizgah , Hayden Lee , Marcel Schmittfull , Cora Dvorkin

Here we review the present status of modelling of and searching for primordial non-Gaussianity of cosmological perturbations. After introducing the models for non-Gaussianity generation during inflation, we discuss the search for…

Cosmology and Nongalactic Astrophysics · Physics 2018-12-21 Marco Celoria , Sabino Matarrese

We investigate the non-Gaussianity of second-order matter density perturbations induced by primordial gravitational waves (GWs). These tensor-induced scalar modes arise from local fluctuations in the GWs energy density, which is quadratic…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-12 Mariam Abdelaziz , Pritha Bari , Sabino Matarrese , Angelo Ricciardone

The generation of white noise on large scales is a generic property of the dynamics of physical systems described by local non-linear partial differential equations. Non-linearities prevent the small scale dynamics from being erased by…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-26 Gabriela Barenboim , Aurora Ireland , Albert Stebbins

In the last few decades, advances in observational cosmology have given us a standard model of cosmology. We know the content of the universe to within a few percent. With more ambitious experiments on the way, we hope to move beyond the…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-26 Amit P. S. Yadav , Benjamin D. Wandelt

Obtaining tight constraints on primordial non-Gaussianity (PNG) is a key step in discriminating between different models for cosmic inflation. The constraining power from large-scale structure (LSS) measurements is expected to overtake that…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-25 James Morawetz , Enrique Paillas , Will J. Percival

The presence of additional particles during inflation leads to non-Gaussianity in late-time correlators of primordial curvature perturbations. The shape and amplitude of this signal depend on the mass and spin of the extra particles.…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-16 Azadeh Moradinezhad Dizgah , Cora Dvorkin

We derive a general expression for the probability of observing deviations from statistical isotropy in the cosmic microwave background (CMB) if the primordial fluctuations are non-Gaussian and extend to superhorizon scales. The primary…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-27 Saroj Adhikari , Sarah Shandera , Adrienne L. Erickcek

We study Minkowski Functionals as probes of primordial non-Gaussianity in the Cosmic Microwave Background, specifically for the estimate of the primordial `local' bi-spectrum parameter f_NL, with instrumental parameters which should be…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Anne Ducout , François Bouchet , Stéphane Colombi , Dmitri Pogosyan , Simon Prunet

Local non-Gaussianities in the initial conditions of the Universe, parameterized by $f_{\rm NL}$, induce a scale-dependence in the large-scale bias of halos in the late Universe. This effect is a promising path to constrain multi-field…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-04 Fiona McCarthy , Mathew S. Madhavacheril , Abhishek S. Maniyar

Relativistic effects in clustering observations have been shown to introduce scale-dependent corrections to the galaxy over-density field on large scales, which may hamper the detection of primordial non-Gaussianity $f_\textrm{NL}$ through…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-14 Mike Shengbo Wang , Florian Beutler , David Bacon
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