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Related papers: A New Approach to Probing Primordial Non-Gaussiani…

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We describe a novel approach to the detection and parameter estimation of a non\textendash Gaussian stochastic background of gravitational waves. The method is based on the determination of relevant statistical parameters using importance…

General Relativity and Quantum Cosmology · Physics 2023-08-22 Riccardo Buscicchio , Anirban Ain , Matteo Ballelli , Giancarlo Cella , Barbara Patricelli

Upcoming galaxy redshift surveys promise to significantly improve current limits on primordial non-Gaussianity (PNG) through measurements of 2- and 3-point correlation functions in Fourier space. However, realizing the full potential of…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-19 Azadeh Moradinezhad Dizgah , Matteo Biagetti , Emiliano Sefusatti , Vincent Desjacques , Jorge Noreña

Brightness-temperature fluctuations in the redshifted 21-cm background from the cosmic dark ages are generated by irregularities in the gas-density distribution and can then be used to determine the statistical properties of density…

Astrophysics · Physics 2008-11-26 Annalisa Pillepich , Cristiano Porciani , Sabino Matarrese

We develop a new formalism for the component separation method Spectral Matching Independent Component Analysis (SMICA) in order to include the information contained in the foregrounds beyond second-order statistics. We also develop a…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-19 M. Citran , H. V. Tran , G. Patanchon , B. van Tent

We investigate the relative sensitivities of several tests for deviations from Gaussianity in the primordial distribution of density perturbations. We consider models for non-Gaussianity that mimic that which comes from inflation as well as…

Astrophysics · Physics 2009-10-31 Licia Verde , Raul Jimenez , Marc Kamionkowski , Sabino Matarrese

Primordial non-Gaussianity is a sensitive probe of the inflationary era, with a number of important theoretical targets living an order of magnitude beyond the reach of current CMB constraints. Maps of the large-scale structure of the…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-07 Daniel Baumann , Daniel Green

We investigate the power of geometrical estimators on detecting non-Gaussianity in the cosmic microwave background. In particular the number, eccentricity and Gaussian curvature of excursion sets above (and below) a threshold are studied.…

Astrophysics · Physics 2011-05-10 R. B. Barreiro , E. Martinez-Gonzalez , J. L. Sanz

As the quality of cosmological data continue to improve, it is natural to test the statistics of primordial fluctuations: are they Gaussian or non-Gaussian? I review a model which generates non-Gaussian adiabatic fluctuations from…

Astrophysics · Physics 2009-10-31 D. S. Salopek

Although cosmological observations suggest that the fluctuations of seed fields are almost Gaussian, the possibility of a small deviation of their fields from Gaussianity is widely discussed. Theoretically, there exist numerous inflationary…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-21 Maresuke Shiraishi

Why is non-Gaussianity interesting? One of generic predictions from inflationary scenarios is that primordial fluctuations are exactly Gaussian in linear order; however, the non-linearity in the inflation will produce weak non-Gaussianity.…

Astrophysics · Physics 2017-08-23 Eiichiro Komatsu , David N. Spergel

Future Large Scale Structure surveys are expected to improve over current bounds on primordial non-Gaussianity (PNG), with a significant impact on our understanding of early Universe physics. The level of such improvements will however…

The bispectrum vanishes for linear Gaussian fields and is thus a sensitive probe of non-linearities and non-Gaussianities in the cosmic density field. Hence, a detection of the bispectrum in the halo density field would enable tight…

Cosmology and Nongalactic Astrophysics · Physics 2011-08-18 Tobias Baldauf , Uros Seljak , Leonardo Senatore

We investigate optimization strategies to measure primordial non-Gaussianity with future spectroscopic surveys. We forecast measurements coming from the 3D galaxy power spectrum and compute constraints on primordial non-Gaussianity…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-26 Alvise Raccanelli , Olivier Dore , Neal Dalal

We explore possible non-Gaussian features of primordial gravitational waves by constructing model-independent templates for nonlinearity parameters of tensor bispectrum. Our analysis is based on Effective Field Theory of inflation that…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-16 Abhishek Naskar , Supratik Pal

Primordial non-Gaussianity is one of the most powerful probes of the inflationary epoch. The particle spectrum relevant to inflation, including masses and spins, is encoded in the precise form of statistical correlations of the adiabatic…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-03 Eugene Chen , Daniel Green , Vincent S. H. Lee

We present a systematic study of galaxy biasing in the presence of primordial non-Gaussianity. For a large class of non-Gaussian initial conditions, we define a general bias expansion and prove that it is closed under renormalization,…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-06 Valentin Assassi , Daniel Baumann , Fabian Schmidt

In this paper we propose a new statistic capable of detecting non-Gaussianity in the CMB. The statistic is defined in Fourier space, and therefore naturally separates angular scales. It consists of taking another Fourier transform, in…

Astrophysics · Physics 2010-04-08 Alex Lewin , Andreas Albrecht , Joao Magueijo

We discuss models of primordial density perturbations where the non-Gaussianity is strongly scale-dependent. In particular, the non-Gaussianity may have a sharp cut-off and be very suppressed on large cosmological scales, but sizeable on…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-18 Antonio Riotto , Martin S. Sloth

We forecast constraints on primordial non-Gaussianity achievable from forthcoming surveys by exploiting the scale-dependent halo bias introduced on large scales by non-Gaussian initial conditions. We explore the performance of exploiting…

Astrophysics · Physics 2010-03-26 Carmelita Carbone , Licia Verde , Sabino Matarrese