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We explore the possibility of putting constraints on dark energy models with statistical property of large scale structure in the non-linear region. In particular, we investigate the $w$ dependence of non-Gaussianity of the smoothed density…

天体物理学 · 物理学 2010-10-27 Takayuki Tatekawa , Shuntaro Mizuno

We computed the power spectrum of weak cosmic shear in models with non-Gaussian primordial density fluctuations. Cosmological initial conditions deviating from Gaussianity have recently attracted much attention in the literature, especially…

宇宙学与河外天体物理 · 物理学 2015-05-14 C. Fedeli , L. Moscardini

Non-Gaussianity indicates complex dynamics related to extreme events or significant outliers. However, the correlation between non-Gaussianity and the dynamics of heterogeneous environments in anomalous diffusion remains uncertain. Inspired…

软凝聚态物质 · 物理学 2023-11-22 Haolan Xu , Xu Zheng , Xinghua Shi

We study the statistical inference of the cosmological dark matter density field from non-Gaussian, non-linear and non-Poisson biased distributed tracers. We have implemented a Bayesian posterior sampling computer-code solving this problem…

宇宙学与河外天体物理 · 物理学 2014-07-01 Metin Ata , Francisco-Shu Kitaura , Volker Müller

The power spectrum of weak lensing fluctuations has a non-Gaussian distribution due to its quadratic nature. On small scales the Central Limit Theorem acts to Gaussianize this distribution but non-Gaussianity in the signal due to…

宇宙学与河外天体物理 · 物理学 2022-06-29 Alex Hall , Andy Taylor

We employ negentropy ($J$), defined as the difference between the information content of a non-Gaussian probability distribution and a Gaussian with identical variance, as an information-theoretic probe of non-Gaussianity in the cosmic…

宇宙学与河外天体物理 · 物理学 2026-02-03 Suman Sarkar

Using the 5 year WMAP data, we re-investigate claims of non-Gaussianities and asymmetries detected in local curvature statistics of the 1 year WMAP data. In Hansen et al 2004, it was found that the northern ecliptic hemisphere was…

宇宙学与河外天体物理 · 物理学 2015-05-18 Øystein Rudjord , Nicolaas E. Groeneboom , Frode K. Hansen , Paolo Cabella

In quintessence models, the dark energy content of the universe is described by a slowly rolling scalar field whose pressure and energy density obey an equation of state of the form p=w $\rho$; w is in general a function of time such that…

天体物理学 · 物理学 2009-11-07 M. Viel , S. Matarrese , Tom Theuns , D. Munshi , Yun Wang

Recent redshift-distance measurements of Type Ia supernovae (SNe Ia) at cosmological distances suggest that two-third of the energy density of the universe is dominated by dark energy component with an effective negative pressure. This dark…

天体物理学 · 物理学 2009-11-06 Deepak Jain , Abha Dev , N. Panchapakesan , S. Mahajan , V. B. Bhatia

We study the non-Gaussian tail of the probability distribution function of density in cosmological N-Body simulations for a variety of initial conditions. We compare the behaviour of the non-Gaussian tail in the real space with that in the…

天体物理学 · 物理学 2007-05-23 J. S. Bagla , Suryadeep Ray

We present N-body simulation calculations of the dependence of the power spectrum of non-linear cosmological mass density fluctuations on the equation of state of the dark energy, w=p/rho. At fixed linear theory power, increasing w leads to…

天体物理学 · 物理学 2009-11-11 Patrick McDonald , Hy Trac , Carlo Contaldi

A non-Gaussian detection in the WMAP 1-year data is reported. The detection has been found in the combined Q-V-W map proposed by the WMAP team (Komatsu et al. 2003) after applying a wavelet technique based on the Spherical Mexican Hat…

天体物理学 · 物理学 2008-11-26 P. Vielva , E. Martinez-Gonzalez , R. B. Barreiro , J. L. Sanz , L. Cayon

We compare different nonlinear approximations to gravitational clustering in the weakly nonlinear regime, using as a comparative statistic the evolution of non-Gaussianity which can be characterised by a set of numbers $S_p$ describing…

天体物理学 · 物理学 2009-10-22 Dipak Munshi , Varun Sahni , Alexei A. Starobinsky

We present a search for non-Gaussianity in the WMAP first-year data using the two-point correlation function of maxima and minima in the temperature map. We find evidence for non-Gaussianity on large scales, whose origin appears to be…

天体物理学 · 物理学 2009-11-13 R. Tojeiro , P. G. Castro , A. F. Heavens , S. Gupta

This is a review of models of inflation and of their predictions for the primordial non-Gaussianity in the density perturbations which are thought to be at the origin of structures in the Universe. Non-Gaussianity emerges as a key…

天体物理学 · 物理学 2009-11-10 N. Bartolo , E. Komatsu , S. Matarrese , A. Riotto

We use the local curvature to investigate the possible existence of non-Gaussianity/asymmetry in the WMAP data. Considering the full sky we find results which are consistent with the Gaussian assumption. However, strong non-Gaussian…

天体物理学 · 物理学 2010-04-06 Frode K. Hansen , Paolo Cabella , Domenico Marinucci , Nicola Vittorio

Gaussian cosmic microwave background skies are fully specified by the power spectrum. The conventional method of characterizing non-Gaussian skies is to evaluate higher order moments, the n-point functions and their Fourier transforms. We…

天体物理学 · 物理学 2011-05-10 Pedro G. Ferreira , Joao Magueijo

The velocity distributions of stellar tracers in general exhibit weak non-Gaussianity encoding information on the orbital composition of a galaxy and the underlying potential. The standard solution for measuring non-Gaussianity involves…

星系天体物理 · 物理学 2020-10-28 Jason L. Sanders , N. Wyn Evans

Non-Gaussian statistics in the distribution of large scale structure, and in temperature fluctuations of the cosmic microwave background, can be used to constrain inflationary models. Data on the cosmic microwave background from Planck…

广义相对论与量子宇宙学 · 物理学 2018-03-06 Nick Woods

We examine the prospect of using the observed abundance of weak gravitational lenses to constrain the equation-of-state parameter w of the dark energy. Here we solve the spherical-collapse model with dark energy, clarifying some ambiguities…

天体物理学 · 物理学 2009-11-07 Nevin N. Weinberg , Marc Kamionkowski
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