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Local primordial non-Gaussianity, parameterised as $f_{\rm NL}^{\rm local}$, will be stringently constrained using state-of-the-art methods applied to next-generation galaxy redshift survey data. In this paper, in preparation for the…

We constrain the primordial non-Gaussianity parameter of the local model f_{NL} using the skewness power spectrum associated with the two-to-one cumulant correlator of cosmic microwave background temperature anisotropies. This…

Cosmology and Nongalactic Astrophysics · Physics 2010-07-22 Joseph Smidt , Alexandre Amblard , Paolo Serra , Asantha Cooray

Motivated by the properties of early universe scenarios that produce observationally large local non-Gaussianity, we perform N-body simulations with non-Gaussian initial conditions from a generalized local ansatz. The bispectra are…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-18 Sarah Shandera , Neal Dalal , Dragan Huterer

Primordial, non-Gaussian perturbations can generate scale-dependent bias in the galaxy distribution. This in turn will modify correlations between galaxy positions and peculiar velocities at late times, since peculiar velocities reflect the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Yin-Zhe Ma , James E. Taylor , Douglas Scott

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

We analyze multi-field inflationary systems which yield strongly scale dependent non-Gaussianity with a shape that is very close to the local shape. As in usual multi-field models, the non-Gaussianity arises from the non-linear transfer of…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-27 Jason Kumar , Louis Leblond , Arvind Rajaraman

We study constraints on primordial mode-coupling from the power spectrum, squeezed-limit bispectrum and collapsed trispectrum of matter and halos. We describe these statistics in terms of long-wavelength $2$-point functions involving the…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-20 Roland de Putter

Quasi-single field inflation predicts a peculiar momentum dependence in the squeezed limit of the primordial bispectrum which smoothly interpolates between the local and equilateral models. This dependence is directly related to the mass of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Emiliano Sefusatti , James R. Fergusson , Xingang Chen , E. P. S. Shellard

We investigate the statistical power of higher-order statistics and cross-correlation statistics to constrain the primordial non-Gaussianity from the imaging surveys. In particular, we consider the local-type primordial non- Gaussianity and…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-08 Ichihiko Hashimoto , Atsushi Taruya , Takahiko Matsubara , Toshiya Namikawa , Shuichiro Yokoyama

Non-Gaussianity of the primordial curvature perturbations may arise from a variety of well motivated early Universe scenarios. In particular, inflationary theories with additional light degrees of freedom can generate a bispectrum that is…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-01 Peter Adshead , Avery J. Tishue

In this work we explore the power of future large-scale surveys to constrain possible deviations from the standard single-field slow-roll inflationary scenario. Specifically, we parametrize possible fluctuations around the almost…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-14 Muhammad Sadegh Esmaeilian , Marzieh Farhang , Shirin Khodabakhshi

Measuring the small primordial nonGaussianity (PNG) predicted by cosmic inflation theories may help diagnose them. The detectability of PNG by its imprint on the 21cm power spectrum from the epoch of reionization is reassessed here in terms…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Yi Mao , Anson D'Aloisio , Jun Zhang , Paul R. Shapiro

We present a new method to constrain local primordial non-Gaussianity using the large-scale modulation of the local lensing power spectrum. Our work extends our recently proposed $\pi$-field method for primordial non-Gaussianity estimation…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-06 Shi-Hui Zang , Moritz Münchmeyer

The statistics of large-scale structure in the Universe can be used to probe non-Gaussianity of the primordial density field, complementary to existing constraints from the cosmic microwave background. In particular, the scale dependence of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Gianmassimo Tasinato , Matteo Tellarini , Ashley J. Ross , David Wands

Single field inflationary models predict nearly Gaussian initial conditions and hence a detection of non-Gaussianity would be a signature of the more complex inflationary scenarios. In this paper we study the effect on the cosmic microwave…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-02 Dmitriy Tseliakhovich , Christopher Hirata , Anze Slosar

We study the effect of primordial non-Gaussianity on the development of large-scale cosmic structure using high-resolution N-body simulations. In particular, we focus on the topological properties of the "cosmic web", quantitatively…

We consider cosmological inflationary models in which vector fields play some role in the generation of the primordial curvature perturbation $\zeta$. Such models are interesting because the involved vector fields naturally seed statistical…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-19 Juan P. Beltran Almeida , Yeinzon Rodriguez , Cesar A. Valenzuela-Toledo

Tighter constraints on measurements of primordial non-Gaussianity will allow the differentiation of inflationary scenarios. The cosmic microwave background bispectrum-the standard method of measuring the local non-Gaussianity-is limited by…

Cosmology and Nongalactic Astrophysics · Physics 2020-09-15 Zahra Gomes , Stefano Camera , Matt J. Jarvis , Catherine Hale , José Fonseca

Upcoming galaxy surveys aim to map the Universe with unprecedented precision, depth and sky coverage. The galaxy bispectrum is a prime source of information as it allows us to probe primordial non-Gaussianity (PNG), a key factor in…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-20 Samantha Rossiter , Stefano Camera , Chris Clarkson , Roy Maartens

In this work we study the large scale structure bias in models of anisotropic inflation. We use the Peak Background Splitting method in Excursion Set Theory to find the scale-dependent bias. We show that the amplitude of the bias is…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Shant Baghram , Mohammad Hossein Namjoo , Hassan Firouzjahi