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相关论文: CMB Anisotropy in Compact Hyperbolic Universes II:…

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We perform detailed calculations of cosmic microwave background (CMB) anisotropies in a CDM-dominated open universe with primordial adiabatic density perturbations for a variety of reionization histories. We show that to a great extent, the…

天体物理学 · 物理学 2009-10-22 Marc Kamionkowski , David N. Spergel , Naoshi Sugiyama

We impose constraints on the topology of the Universe determined from a search for matched circles in the cosmic microwave background (CMB) temperature anisotropy patterns of the 7-year WMAP data. We pay special attention to the sensitivity…

宇宙学与河外天体物理 · 物理学 2013-03-19 P. Bielewicz , A. J. Banday , K. M. Gorski

The standard cosmological model predicts statistically isotropic cosmic microwave background (CMB) fluctuations characterized by the CMB temperature coefficients $a_{\ell m}$ being independent Gaussian random variables with zero mean and…

宇宙学与河外天体物理 · 物理学 2026-03-17 Joann Jones , Craig J. Copi , Glenn D. Starkman , Yashar Akrami

When considering the statistical properties of a bundle of cosmic microwave background (CMB) photons propagating through space, the effect of `mixing geodesics' appears with a distinct signature that depends on the geometry of space. In a…

天体物理学 · 物理学 2011-05-10 V. G. Gurzadyan , S. Torres

The breakdown of statistical homogeneity and isotropy of cosmic perturbations is a generic feature of ultra large scale structure of the cosmos, in particular, of non trivial cosmic topology. The statistical isotropy (SI) of the Cosmic…

天体物理学 · 物理学 2007-05-23 Amir Hajian , Tarun Souradeep

We have simulated cosmic microwave background (CMB) anisotropy maps for several COBE-DMR-normalized cold dark matter (CDM) cosmogonies, to make predictions for the upcoming MAP experiment. We have studied the sensitivity of the simulated…

Unexpected features have been observed in the cosmic microwave background (CMB) temperature on large scales. We revisit these CMB anomalies using new foreground-cleaned CMB temperature maps derived in a companion paper from WMAP and Planck…

宇宙学与河外天体物理 · 物理学 2025-09-05 Laura Herold , Graeme E. Addison , Charles L. Bennett , Hayley C. Nofi , J. L. Weiland

Most parameter constraints obtained from cosmic microwave background (CMB) anisotropy data are based on power estimates and rely on approximate likelihood functions; computational difficulties generally preclude an exact analysis based on…

天体物理学 · 物理学 2009-11-06 M. Douspis , J. G. Bartlett , A. Blanchard , M. Le Dour

We compute the cosmic microwave background (CMB) anisotropy in a low-density, flat, cosmological constant, cold dark matter model which is normalized to the two-year COBE DMR sky map. Although conclusions regarding model viability must…

天体物理学 · 物理学 2015-06-24 Bharat Ratra , Naoshi Sugiyama

I review the basic theory of the cosmic microwave background anisotropies in adiabatic cold dark matter cosmologies. The latest observational results on the CMB power spectrum are consistent with the simplest inflationary models and…

天体物理学 · 物理学 2009-09-25 G. Efstathiou

The presence of astrophysical emissions between the last scattering surface and our vantage point requires us to apply a foreground mask on CMB sky map, leading to large cut around the Galactic equator and numerous holes. Since many CMB…

宇宙学与河外天体物理 · 物理学 2012-04-17 Jaiseung Kim , Pavel Naselsky , Nazzareno Mandolesi

The properties of the Cosmic Microwave Background (CMB) radiation must be different in flat, positively and negatively curved universes. This fact leads to a direct way of determining the geometry of the universe. The signature of the…

天体物理学 · 物理学 2018-03-28 V. G. Gurzadyan

We revisit the observational constraints on compact(closed) hyperbolic(CH) models from cosmic microwave background(CMB). We carry out Bayesian analyses for CH models with volume comparable to the cube of the present curvature radius using…

天体物理学 · 物理学 2009-11-06 Kaiki Taro Inoue

Although the cubic T^3 "small universe" has been ruled out by COBE/DMR results as an interesting cosmological model, we still have the possibility of living in a universe with a more anisotropic topology such as a rectangular T^3 "small…

天体物理学 · 物理学 2009-10-28 Angelica de Oliveira-Costa , George F. Smoot , Alexei A. Starobinsky

The origin of power asymmetry and other measures of statistical anisotropy on the largest scales of the universe, as manifested in Cosmic Microwave Background (CMB) and large-scale structure data, is a long-standing open question in…

宇宙学与河外天体物理 · 物理学 2021-05-12 Pablo Fosalba , Enrique Gaztanaga

The current suite of results from Cosmic Microwave Background anisotropy experiments is fulfilling the promise of providing extraordinary levels of discrimination between cosmological models. We calculate a binned anisotropy power spectrum,…

天体物理学 · 物理学 2007-05-23 Elena Pierpaoli , Douglas Scott , Martin White

We use simulated maps of the cosmic microwave background anisotropy to quantify the ability of different statistical tests to discriminate between Gaussian and non-Gaussian models. Despite the central limit theorem on large angular scales,…

天体物理学 · 物理学 2009-10-31 Nicholas G. Phillips , A. Kogut

On large angular scales (greater than about 60 degrees), the two-point angular correlation function of the temperature of the cosmic microwave background (CMB), as measured (outside of the plane of the Galaxy) by the Wilkinson Microwave…

宇宙学与河外天体物理 · 物理学 2015-05-18 Devdeep Sarkar , Dragan Huterer , Craig J. Copi , Glenn D. Starkman , Dominik J. Schwarz

Analyses of recent cosmic microwave background (CMB) observations have provided increasing indications for the existence of large scale anisotropy in the universe. Given the far reaching consequences of such an anisotropy for our…

天体物理学 · 物理学 2009-09-29 A. Bernui , B. Mota , M. J. Reboucas , R. Tavakol

The majority of present efforts to constrain cosmological parameters with cosmic microwave background (CMB) anisotropy data employ approximate likelihood functions, the time consuming nature of a complete analysis being a major obstacle. We…

天体物理学 · 物理学 2007-05-23 M. Douspis , J. G. Bartlett , A. Blanchard , M. Le Dour