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Related papers: Kurtosis and Large--Scale Structure

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A sizeable level of non-Gaussianity in the primordial cosmological perturbations may be induced by a large trispectrum, i.e. by a large connected four-point correlation function. We compute the effect of a primordial non-Gaussian…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Michele Maggiore , Antonio Riotto

We revise the Non-Gaussianity of canonical curvaton scenario with a generalized $\delta N$ formalism, in which it could handle the generic potentials. In various curvaton models, the energy density is dominant in different period including…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-18 Lei-Hua Liu , Bin Liang , Ya-Chen Zhou , Xiao-Dan Liu , Wu-Long Xu , Ai-Chen Li

The redshift dependence of the abundance of galaxy clusters is very sensitive to the statistical properties of primordial density perturbations. It can thus be used to probe small deviations from Gaussian initial conditions. Such deviations…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 A. M. M. Trindade , P. P. Avelino , P. T. P. Viana

This paper examines the growth of dark matter and dark energy perturbations within a non-canonical scalar field model characterized by an exponential potential. Through dynamical system analysis, we identify critical points and track the…

General Relativity and Quantum Cosmology · Physics 2025-10-21 Zanyar Ebrahimi , Kayoomars Karami

We find statistical evidence for a mismatch between the (global) spatial curvature parameter $K$ in the geodesic equation for incoming photons, and the corresponding parameter in the Friedmann equation that determines the time evolution of…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-04 Meir Shimon , Yoel Rephaeli

Is gravitational growth responsible for the observed large scale structure in the universe? Do we need non-gaussian initial conditions or non-gravitational physics to explain the large scale features traced by galaxy surveys? I will briefly…

Astrophysics · Physics 2007-05-23 Enrique Gaztanaga

We obtain constraints on the variation of the fundamental constants from the full shape of the redshift-space correlation function of a sample of luminous galaxies drawn from the Data Release 9 of the Baryonic Oscillations Spectroscopic…

Using numerical simulations, we investigate the large-scale gravitational clustering in a flat universe dominated by cold plus hot dark matter (i.e., $\Omega_0=\ocdm+\ohdm+\obaryon=1$). Primordial density fluctuation spectrum is taken to…

Astrophysics · Physics 2010-12-09 Y. P. Jing , H. J. Mo , G. Boerner , L. Z. Fang

We suggest here a mechanism for the seeding of the primordial density fluctuations. We point out that a process like reheating at the end of inflation will inevitably generate perturbations, even on superhorizon scales, by the local…

Cosmology and Nongalactic Astrophysics · Physics 2009-05-01 Richard Lieu , T. W. B. Kibble

The cosmic web is a complex spatial pattern of walls, filaments, cluster nodes and underdense void regions. It emerged through gravitational amplification from the Gaussian primordial density field. Here we infer analytical expressions for…

Cosmology and Nongalactic Astrophysics · Physics 2014-12-17 Job Feldbrugge , Johan Hidding , Rien van de Weygaert

We investigate future constraints on primordial local-type non-Gaussianity from 21 cm angular power spectrum from minihalos. We particularly focus on the trispectrum of primordial curvature perturbations which are characterized by the…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-27 Toyokazu Sekiguchi , Tomo Takahashi , Hiroyuki Tashiro , Shuichiro Yokoyama

The impact of the third (skewness) and fourth (kurtosis) reduced centered moments on the statistical modeling of E1 lines in complex atomic spectra is investigated through the use of Gram-Charlier, Normal Inverse Gaussian and Generalized…

Atomic Physics · Physics 2015-05-13 Jean-Christophe Pain , Franck Gilleron , Jacques Bauche , Claire Bauche-Arnoult

We calculate the power spectrum of density fluctuations in the statistical non-equilibrium field theory for classical, microscopic degrees of freedom to first order in the interaction potential. We specialise our result to cosmology by…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-07 Matthias Bartelmann , Felix Fabis , Daniel Berg , Elena Kozlikin , Robert Lilow , Celia Viermann

It has been shown that the large--scale correlation functions of the density field (and velocity divergence field) follow a specific hierarchy in the quasilinear regime and for Gaussian initial conditions (Bernardeau 1992). The exact…

Astrophysics · Physics 2007-05-23 F. Bernardeau

Bouchet et al. (1992) showed that in an open or closed Universe with only pressureless matter, gravitational instability from Gaussian initial conditions induces a normalized skewness, $S_3 \equiv \VEV{\delta^3} \VEV{\delta^2}^{-2}$, that…

Astrophysics · Physics 2009-10-30 M. Kamionkowski , A. Buchalter

We use the number density of peaks in the smoothed cosmological density field taken from the 2dF Galaxy Redshift Survey to constrain parameters related to the power spectrum of mass fluctuations, n (the spectral index), dn/d(lnk) (rolling…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 S. De , R. A. C. Croft

We derive a non-perturbative, closed, analytic equation for the non-linear power spectrum of cosmic density fluctuations. This result is based on our kinetic field theory (KFT) of cosmic structure formation and on evaluating particle…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-23 Matthias Bartelmann , Felix Fabis , Sara Konrad , Elena Kozlikin , Robert Lilow , Carsten Littek , Johannes Dombrowski

The shape of the primordial fluctuation spectrum is probed by cosmic microwave background fluctuations which measure density fluctuations at z~1000 on scales of hundreds of Mpc and from galaxy redshift surveys, which measure structure at…

Astrophysics · Physics 2014-10-13 Joseph Silk , Eric Gawiser

We point out that the quartic cumulant (and kurtosis) of the order parameter fluctuations is universally negative when the critical point is approached on the crossover side of the phase separation line. As a consequence, the kurtosis of a…

High Energy Physics - Phenomenology · Physics 2015-03-19 M. A. Stephanov

We conduct a thorough study of the comoving curvature perturbation $\mathcal{R}$ in single-field inflation with two stages, represented by a piecewise quadratic potential, where both the first and second derivatives are allowed to be…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-23 Xinpeng Wang , Xiao-Han Ma , Misao Sasaki