English
Related papers

Related papers: Constraining the initial conditions of the Univers…

200 papers

The ability to differentiate between different models of inflation through the imprint of primordial non-Gaussianity (PNG) requires stringent constraints on the local PNG parameter $f_{\text{NL}}^{\text{loc}}$. Upcoming data from the large…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-16 Chandra Shekhar Saraf , David Parkinson

Local primordial non-Gaussianity (LPNG) is predicted by many non-minimal models of inflation, and creates a scale-dependent contribution to the power spectrum of large-scale structure (LSS) tracers, whose amplitude is characterized by…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-11 James M Sullivan , Tijan Prijon , Uros Seljak

Recent studies have shown that the primordial non-Gaussianity affects clustering of dark matter halos through a scale-dependent bias and various constraints on the non-Gaussianity through this scale-dependent bias have been placed. Here we…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-02 Yoshitaka Takeuchi , Kiyotomo Ichiki , Takahiko Matsubara

The large-scale structure of the universe suggests that the physics underlying its early evolution is scale-free. This was the historic motivation for the Harrison-Zel'dovich-Peebles spectrum and for inflation. Based on a hydrodynamical…

Cosmology and Nongalactic Astrophysics · Physics 2014-02-03 Anna Ijjas , Paul J. Steinhardt , Abraham Loeb

We investigate the effect of primordial non-Gaussianities on halo number counts using N-body simulations with different values of $f_{\rm NL}^{\rm loc}$. We show how current theoretical models fail to adequately describe the non-Gaussian…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-30 Luca Fiorino , Sofia Contarini , Federico Marulli , Ariel G. Sanchez , Marco Baldi , Andrea Fiorilli , Lauro Moscardini

We extend an alternative, phenomenological approach to inflation by means of an equation of state and a sound speed, both of them functions of the number of $e$-folds and four phenomenological parameters. This approach captures a number of…

Cosmology and Nongalactic Astrophysics · Physics 2020-12-10 Stefano Gariazzo , Olga Mena , Hector Ramirez , Lotfi Boubekeur

Single-field models of $\alpha$-attractor quintessential inflation provide a unified picture of the two periods of early- and late-time cosmic acceleration, where both inflation and dark energy are described by a single scalar degree of…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-05 Yashar Akrami , Santiago Casas , Senwen Deng , Valeri Vardanyan

The kinetic Sunyaev Zel'dovich effect is a secondary CMB temperature anisotropy that provides a powerful probe of the radial-velocity field of matter distributed across the Universe. This velocity field is reconstructed by combining…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-31 Neha Anil Kumar , Gabriela Sato-Polito , Marc Kamionkowski , Selim C. Hotinli

We study the statistical descriptors for some cosmological inflationary models that allow us to get large levels of non-gaussianity and violations of statistical isotropy. Basically, we study two different class of models: a model that…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-05 Cesar A. Valenzuela-Toledo

We use cosmological N-body simulations to investigate whether measurements of the moments of large-scale structure can yield constraints on primordial non-Gaussianity. We measure the variance, skewness, and kurtosis of the evolved density…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-24 Qingqing Mao , Andreas A. Berlind , Cameron K. McBride , Robert J. Scherrer , Roman Scoccimarro , Marc Manera

We present primordial non-Gaussianity predictions from a new high-precision code for simulating axion-U(1) inflation on a discrete lattice. We measure the primordial scalar curvature power spectrum and bispectrum from our simulations,…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-26 Drew Jamieson , Angelo Caravano , Eiichiro Komatsu

We show how observations of the evolution of the galaxy cluster number abundance can be used to constrain primordial non-Gaussianity in the universe. We carry out a maximum likelihood analysis incorporating a number of current datasets and…

Astrophysics · Physics 2009-10-31 James Robinson , Eric Gawiser , Joseph Silk

Using the quantum information picture to describe the early universe as a time dependent quantum density matrix, with time playing the role of a stochastic variable, we compute the non-gaussian features in the distribution of primordial…

Cosmology and Nongalactic Astrophysics · Physics 2021-10-19 Cesar Gomez , Raul Jimenez

We studied the effect of primordial non-Gaussianity with varied bispectrum shapes on the number counts of signal-to-noise peaks in wide field cosmic shear maps. The two cosmological contributions to this particular weak lensing statistic,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 M. Maturi , C. Fedeli , L. Moscardini

Primordial non-Gaussianity is a crucial test of inflationary cosmology. We consider the impact of non-Gaussianity on the ionization power spectrum from 21 cm emission during the epoch of reionization. We focus on the power spectrum on large…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-30 Shahab Joudaki , Olivier Dore , Luis Ferramacho , Manoj Kaplinghat , Mario G. Santos

We forecast the constraints on single-field inflation from the bispectrum of future high-redshift surveys such as MegaMapper. Considering non-local primordial non-Gaussianity (NLPNG), we find that current methods will yield constraints of…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-06 Giovanni Cabass , Mikhail M. Ivanov , Oliver H. E. Philcox , Marko Simonovic , Matias Zaldarriaga

One of the main signatures of primordial non-Gaussianity of the local type is a scale-dependent correction to the bias of large-scale structure tracers such as galaxies or clusters, whose amplitude depends on the bias of the tracers itself.…

Cosmology and Nongalactic Astrophysics · Physics 2012-01-11 Nico Hamaus , Uros Seljak , Vincent Desjacques

We study the scale dependent bias of the halo power spectrum arising from primordial non-Gaussianity. We present an analytic result of the halo bias including up to the trispectrum contributions. We find the scale dependent bias opens a new…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Jinn-Ouk Gong , Shuichiro Yokoyama

We review the relevant 10+ parameters associated with inflation and matter content; the relation between LSS and primary and secondary CMB anisotropy probes; COBE constraints on energy injection; current anisotropy band-powers which…

Astrophysics · Physics 2009-10-30 J. Richard Bond , Andrew H. Jaffe