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Related papers: Primordial Non-Gaussianity from LAMOST Surveys

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Any hint of non-gaussianity in the cosmological initial conditions will provide us with a unique window into the physics of early universe. We show that the impact of a small local primordial non-gaussianity (generated on super-horizon…

Astrophysics · Physics 2008-12-18 Niayesh Afshordi , Andrew J. Tolley

Recent second-order perturbation computations have provided an accurate prediction for the primordial gravitational potential $\Phi(x)$ in scenarios in which cosmological perturbations are generated either during or after inflation. This…

Astrophysics · Physics 2008-11-26 M. Liguori , F. K. Hansen , E. Komatsu , S. Matarrese , A. Riotto

We study the impact that uncertainties on assumed relations between galaxy bias parameters have on constraints of the local PNG $f_{\rm NL}$ parameter. We focus on the relation between the linear density galaxy bias $b_1$ and local PNG bias…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-13 Alexandre Barreira

A detection or nondetection of primordial non-Gaussianity by using the cosmic microwave background radiation (CMB) offers a way of discriminating inflationary scenarios and testing alternative models of the early universe. This has…

Cosmology and Nongalactic Astrophysics · Physics 2012-02-15 A. Bernui , M. J. Reboucas , A. F. F. Teixeira

The statistical properties of the primordial perturbations contain clues about the origins of those fluctuations. Although the Planck collaboration has recently obtained tight constraints on primordial non-gaussianity from cosmic microwave…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-09 Adam Lidz , Eric J. Baxter , Peter Adshead , Scott Dodelson

We propose a new probe of primordial non-Gaussianities (NGs) through the observation of gravitational waves (GWs) induced by ultra-light ($M_{\text{PBH}}< 10^{9}\rm{g}$) primordial black holes (PBHs). Interestingly enough, the existence of…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-02 Theodoros Papanikolaou , Xin-Chen He , Xiao-Han Ma , Yi-Fu Cai , Emmanuel N. Saridakis , Misao Sasaki

Local-type primordial non-gaussianity generates a distinctive term in the clustering of tracers of large-scale structure, behaving as $k^{-2}$ at small wavenumbers $k$. In order to use this signal in a sample of galaxies to measure the…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-28 Neal Dalal , Will J. Percival

We apply a suite of different estimators to the Quijote-PNG halo catalogues to find the best approach to constrain Primordial non-Gaussianity (PNG) at non-linear cosmological scales, up to $k_{\rm max} = 0.5 \, h\,{\rm Mpc}^{-1}$. The set…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-04 Gabriel Jung , Andrea Ravenni , Michele Liguori , Marco Baldi , William R. Coulton , Francisco Villaescusa-Navarro , Benjamin D. Wandelt

Local non-Gaussianity, parametrized by $f_{\rm NL}$, introduces a scale-dependent bias that is strongest at large scales, precisely where General Relativistic (GR) effects also become significant. With future data, it should be possible to…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Marco Bruni , Robert Crittenden , Kazuya Koyama , Roy Maartens , Cyril Pitrou , David Wands

Non-local primordial non-Gaussianity (NLPNG) is a smoking gun of interactions in single-field inflationary models, and can be written as a combination of the equilateral and orthogonal templates. We present the first constraints on these…

Cosmology and Nongalactic Astrophysics · Physics 2022-07-20 Giovanni Cabass , Mikhail M. Ivanov , Oliver H. E. Philcox , Marko Simonović , Matias Zaldarriaga

The primordial non-Gaussianity of local type affects the clustering of dark matter halos, and the planned deep and wide photometric surveys are suitable for examining this class of non-Gaussianity. In our previous paper, we investigated the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Yoshitaka Takeuchi , Kiyotomo Ichiki , Takahiko Matsubara

The scale-dependent bias effect on the galaxy power spectrum is a very promising probe of the local primordial non-Gaussianity (PNG) parameter $f_{\rm NL}$, but the amplitude of the effect is proportional to $f_{\rm NL}b_{\phi}$, where…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-11 Alexandre Barreira

New generation galaxy surveys targeting constraints on local primordial non-Gaussianity (PNG) demand $N$-body simulations that accurately reproduce its effects. In this work, we explore various prescriptions for the initial conditions of…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-14 Adrian G. Adame , Santiago Avila , Violeta Gonzalez-Perez , Oliver Hahn , Gustavo Yepes , Marc Manera

We present an upgraded combined estimator, based on Minkowski Functionals and Neural Networks, with excellent performance in detecting primordial non-Gaussianity in simulated maps that also contain a weighted mixture of Galactic…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-07 C. P. Novaes , A. Bernui , I. S. Ferreira , C. A. Wuensche

[Abridged]: A detection or nondetection of primordial non-Gaussianity by using the CMB data is crucial not only to discriminate inflationary models but also to test alternative scenarios. Non-Gaussianity offers, therefore, a powerful probe…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-14 A. Bernui , M. J. Reboucas

We examine the cosmological constraining power of future large-scale weak lensing surveys on the model of \emph{Euclid}, with particular reference to primordial non-Gaussianity. Our analysis considers several different estimators of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 C. Fedeli , M. Bartelmann , L. Moscardini

We present N-body cosmological numerical simulations including a primordial non-Gaussianity in the density fluctuation field quantified by the non-linear parameter $f_{NL}$. We have used MPGRAFIC code to produce initial conditions and the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 F. Fraschetti , J. M. Alimi , J. Courtin , P. S. Corasaniti

Primordial non-Gaussianity is a potentially powerful discriminant of the physical mechanisms that generated the cosmological fluctuations observed today. Any detection of significant non-Gaussianity would thus have profound implications for…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-25 Vincent Desjacques , Uros Seljak

We investigate how much can be learnt about four types of primordial non-Gaussianity (PNG) from small-scale measurements of the halo field. Using the QUIJOTE-PNG simulations, we quantify the information content accessible with measurements…

Characterizing the level of primordial non-Gaussianity (PNG) in the initial conditions for structure formation is one of the most promising ways to test inflation and differentiate among different scenarios. The scale-dependent imprint of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Anson D'Aloisio , Jun Zhang , Donghui Jeong , Paul R. Shapiro