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Related papers: Non-Gaussian Shape Recognition

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The nonlinear parameter measures the amplitude of primordial non-Gaussianity in the cosmic microwave background radiation (CMB), offering a crucial test of early universe models. While standard single field inflation predicts nearly…

Statistics Theory · Mathematics 2025-07-11 Claudio Durastanti

We forecast combined future constraints from the cosmic microwave background and large-scale structure on the models of primordial non-Gaussianity. We study the generalized local model of non-Gaussianity, where the parameter f_NL is…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Adam Becker , Dragan Huterer , Kenji Kadota

We are on the verge of the first precision testing of the inflationary cosmology as a model for the origin of structure in the Universe. I review the key predictions of inflation which can be used as observational tests, in the sense of…

Astrophysics · Physics 2007-05-23 Andrew R Liddle

[Abridged] We consider how galaxy clustering data, from Mpc to Gpc scales, from upcoming large scale structure surveys, such as Euclid and DESI, can provide discriminating information about the bispectrum shape arising from a variety of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Joyce Byun , Rachel Bean

In our previous work the nonlinearity parameter f_NL, which characterizes nongaussianity in the cosmic microwave background, was estimated for a class of inflationary models based on nonlocal field theory. These models include p-adic…

High Energy Physics - Theory · Physics 2009-08-25 Neil Barnaby , James M. Cline

We develop a mathematical construction of non-Gaussian fields whose bispectra satisfy the single-clock inflation consistency relation. At the same order that our basis for bispectra recovers the two simplest single clock templates, we also…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-17 Bekir Baytaş , Sarah Shandera

We present a new independent pipeline for the CMB bispectrum estimation of primordial non-Gaussianity and release a public code for constraining bispectrum shapes of interest based on the Planck 2018 temperature and polarization data. The…

Cosmology and Nongalactic Astrophysics · Physics 2023-10-06 Wuhyun Sohn , James R. Fergusson , E. P. S. Shellard

We compute non-Gaussianities in N-flation, a string motivated model of assisted inflation with quadratic, separable potentials and masses given by the Marcenko-Pastur distribution. After estimating parameters characterizing the bi- and…

High Energy Physics - Theory · Physics 2010-10-27 Diana Battefeld , Thorsten Battefeld

We study brane inflation scenarios in a warped throat geometry and show that there exists a consistency condition between the non-Gaussianity of the curvature perturbation and the amplitude and scale-dependence of the primordial…

Astrophysics · Physics 2008-11-26 James E. Lidsey , David Seery

The issue of non-Gaussianity is not only related to distinguishing the theories of the origin of primordial fluctuations, but also crucial for the determination of cosmological parameters in the framework of inflation paradigm. We present…

Astrophysics · Physics 2009-11-10 Lung-Yih Chiang , Pavel D. Naselsky

While attempting to connect inflationary theories to observational physics, a potential difficulty is the degeneracy problem: a single set of observables maps to a range of different inflaton potentials. Two important classes of models…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Damien A. Easson , Brian A. Powell

The precision reached by the recent CMB measurements gives new insights into the shape of the primordial power spectra of the cosmological perturbations. In the context of inflationary cosmology, this implies that the CMB data are now…

Astrophysics · Physics 2015-10-08 Christophe Ringeval

We study a particular Galileon inflation in the light of Planck2015 observational data in order to constraint the model parameter space. We study the spectrum of the primordial modes of the density perturbations by expanding the action up…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-14 Kosar Asadi , Kourosh Nozari

In this work we effectively calculated the two-dimensional Minkowski functionals for cosmic microwave background (CMB) temperature maps generated by single field models of inflation with a standard kinetic term. We started with calculation…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-25 M. Junaid , D. Pogosyan

A $\delta N$ formalism is used to study the non-Gaussianity of the primordial curvature perturbation on an uniform density hypersurfaces generated by the warm inflation for the first time. After introducing the framework of the warm…

General Relativity and Quantum Cosmology · Physics 2016-04-01 Xiao-Min Zhang , Hong-Yang Ma , Peng-Cheng Chu , Jun-Ting Liu , Jian-Yang Zhu

The Planck CMB experiment has delivered the best constraints so far on primordial non-Gaussianity, ruling out early-Universe models of inflation that generate large non-Gaussianity. Although small improvements in the CMB constraints are…

Inflation driven by a single, minimally coupled, slowly rolling field generically yields a negligible primordial non-Gaussianity. We discuss two distinct mechanisms by which a non-trivial potential can generate large non-Gaussianities.…

Astrophysics · Physics 2009-06-23 Xingang Chen , Richard Easther , Eugene A. Lim

We discuss methods to compute maps of the CMB in models featuring active causal sources and in non-Gaussian models ofinflation. We show our large angle results as well as some preliminary results on small angles. We conclude by discussing…

Astrophysics · Physics 2007-05-23 Martin Landriau , Paul Shellard

It was pointed out recently that in some inflationary models quantum loops containing a scalar of mass $m$ that couples to the inflaton can be the dominant source of primordial non-Gaussianities. We explore this phenomenon in the simplest…

High Energy Physics - Phenomenology · Physics 2019-03-27 Haipeng An , Mark B. Wise , Zipei Zhang

We build upon previous analytical treatments of scalar perturbations in curved inflationary universes to obtain analytical templates for the primordial tensor power spectrum in models with non-zero primordial spatial curvature. These…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-27 Ezra Msolla , Ayngaran Thavanesan
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