中文
相关论文

相关论文: The shape of primordial non-Gaussianity and the CM…

200 篇论文

The measurements of the statistical properties of the Cosmic Microwave Background (CMB) fluctuations enable us to probe the physics of the very early Universe especially at the epoch of inflation. A particular interest lays on the detection…

宇宙学与河外天体物理 · 物理学 2011-06-07 S. Pires , S. Plaszczynski , A. Lavabre

We investigate new shapes of local primordial non-Gaussianities in the CMB. Allowing for a primordial isocurvature mode along with the main adiabatic one, the angular bispectrum is in general a superposition of six distinct shapes: the…

宇宙学与河外天体物理 · 物理学 2015-05-27 David Langlois , Bartjan van Tent

We present a new formalism, together with efficient numerical methods, to directly calculate the CMB bispectrum today from a given primordial bispectrum using the full linear radiation transfer functions. Unlike previous analyses which have…

天体物理学 · 物理学 2008-11-26 J. R. Fergusson , E. P. S. Shellard

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…

宇宙学与河外天体物理 · 物理学 2022-09-21 Maresuke Shiraishi

We use a separable mode expansion estimator with WMAP data to estimate the bispectrum for all the primary families of non-Gaussian models. We review the late-time mode expansion estimator methodology which can be applied to any…

宇宙学与河外天体物理 · 物理学 2015-05-19 J. R. Fergusson , M. Liguori , E. P. S. Shellard

We present trispectrum estimation methods which can be applied to general non-separable primordial and CMB trispectra. We present a general optimal estimator for the connected part of the trispectrum, for which we derive a quadratic term to…

宇宙学与河外天体物理 · 物理学 2014-11-20 D. M. Regan , E. P. S. Shellard , J. R. Fergusson

We present a detailed implementation of two bispectrum estimation methods which can be applied to general non-separable primordial and CMB bispectra. The method exploits bispectrum mode decompositions on the domain of allowed wavenumber or…

宇宙学与河外天体物理 · 物理学 2014-11-20 J. R. Fergusson , M. Liguori , E. P. S. Shellard

A detection of primordial non-Gaussianity could transform our understanding of the fundamental theory of inflation. The precision promised by upcoming CMB and large-scale structure surveys raises a natural question: if a detection given a…

宇宙学与河外天体物理 · 物理学 2014-03-04 Joyce Byun , Rachel Bean

We study the degree to which the cosmic microwave background (CMB) can be used to constrain primordial non-Gaussianity involving one tensor and two scalar fluctuations, focusing on the correlation of one polarization $B$ mode with two…

宇宙学与河外天体物理 · 物理学 2016-06-15 P. Daniel Meerburg , Joel Meyers , Alex van Engelen , Yacine Ali-Haïmoud

After the precise observations of the Cosmic Microwave Background (CMB) anisotropy power spectrum, attention is now being focused on the higher order statistics of the CMB anisotropies. Since linear evolution preserves the statistical…

天体物理学 · 物理学 2009-11-10 Daniel Babich , Matias Zaldarriaga

To efficiently probe primordial non-Gaussianity using Cosmic Microwave Background (CMB) data, we require theoretical predictions that are factorizable, \textit{i.e.}\ those whose kinematic dependence can be separated. This property does not…

宇宙学与河外天体物理 · 物理学 2025-11-25 Oliver H. E. Philcox , Kunhao Zhong , Salvatore Samuele Sirletti

[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…

宇宙学与河外天体物理 · 物理学 2010-04-14 A. Bernui , M. J. Reboucas

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…

宇宙学与河外天体物理 · 物理学 2012-02-15 A. Bernui , M. J. Reboucas , A. F. F. Teixeira

Non-Gaussianity in the distribution of inflationary perturbations, measurable in statistics of the cosmic microwave background (CMB) and large scale structure fluctuations, can be used to probe non-trivial initial quantum states for these…

宇宙学与河外天体物理 · 物理学 2015-06-17 Joyce Byun , Nishant Agarwal , Rachel Bean , Richard Holman

If time-dependent disruptions from slow-roll occur during inflation, the correlation functions of the primordial curvature perturbation should have scale-dependent features, a case which is marginally supported from the cosmic microwave…

宇宙学与河外天体物理 · 物理学 2018-06-04 Jinn-Ouk Gong , Gonzalo A. Palma , Spyros Sypsas

Squeezed primordial non-Gaussianity can strongly constrain early-universe physics, but it can only be observed on the CMB after it has been gravitationally lensed. We give a new simple non-perturbative prescription for accurately…

宇宙学与河外天体物理 · 物理学 2015-03-19 Ruth Pearson , Antony Lewis , Donough Regan

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…

宇宙学与河外天体物理 · 物理学 2023-10-06 Wuhyun Sohn , James R. Fergusson , E. P. S. Shellard

We apply a new method to measure primordial non-Gaussianity, using the cross-correlation between galaxy surveys and the CMB lensing signal to measure galaxy bias on very large scales, where local-type primordial non-Gaussianity predicts a…

宇宙学与河外天体物理 · 物理学 2014-06-06 Tommaso Giannantonio , Will J. Percival

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…

天体物理学 · 物理学 2009-11-10 Lung-Yih Chiang , Pavel D. Naselsky

Next-generation galaxy surveys will be able to measure perturbations on scales beyond the equality scale. On these ultra-large scales, primordial non-Gaussianity leaves signatures that can shed light on the mechanism by which perturbations…

宇宙学与河外天体物理 · 物理学 2019-09-10 Mario Ballardini , William Luke Matthewson , Roy Maartens
‹ 上一页 1 2 3 10 下一页 ›