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相关论文: Do we Live in a "Small Universe"?

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The recent WMAP data represents a milestone in cosmology and helps constrain cosmological parameters with unprecedented accuracy. In this work we combine the WMAP data with previous CMB anisotropy measurements at smaller angular scales to…

天体物理学 · 物理学 2015-06-24 C. J. Odman

It is shown that the recent observations of NASA's explorer mission "Wilkinson Microwave Anisotropy Probe" (WMAP) hint that our Universe may possess a non-trivial topology. As an example we discuss the Picard space which is stretched out…

天体物理学 · 物理学 2009-11-10 R. Aurich , S. Lustig , F. Steiner , H. Then

We present the final nine-year maps and basic results from the WMAP mission. We provide new nine-year full sky temperature maps that were processed to reduce the asymmetry of the effective beams. Temperature and polarization sky maps are…

We reexamine constraints on the spatial size of closed toroidal models with cold dark matter and the cosmological constant from cosmic microwave background. We carry out Bayesian analyses using the Cosmic Background Explorer (COBE) data…

天体物理学 · 物理学 2009-11-07 Kaiki Taro Inoue , Naoshi Sugiyama

While the standard, six-parameter, spatially flat $\Lambda$CDM model has been highly successful, certain anomalies in the cosmic microwave background bring out a tension between this model and observations. The statistical significance of…

广义相对论与量子宇宙学 · 物理学 2021-09-21 Abhay Ashtekar , Brajesh Gupt , V. Sreenath

The temperature anisotropy power spectrum measured with the Wilkinson Microwave Anisotropy Probe (WMAP) at high multipoles is in spectacular agreement with an inflationary Lambda-dominated cold dark matter cosmology. However, the low order…

天体物理学 · 物理学 2009-11-07 G. Efstathiou

Fluctuations in the temperature of the cosmic microwave background have now been detected over a wide range of angular scales, and a consistent picture seems to be emerging. This article describes some of the implications for cosmology.…

天体物理学 · 物理学 2009-10-28 Douglas Scott , Joe Silk , Martin White

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 angular power spectrum of the Cosmic Microwave Background has been measured out to sufficiently small angular scale to encompass a few acoustic oscillations. We use a phenomenological fit to the angular power spectrum to quantify the…

天体物理学 · 物理学 2009-11-07 M. Douspis , P. G. Ferreira

A recent paper (Martinez--Gonzalez & Sanz 1995) showed that if the universe is homogeneous but anisotropic, then the small quadrupole anisotropy in the cosmic microwave background radiation implies that the spacetime anisotropy is very…

天体物理学 · 物理学 2007-05-23 Roy Maartens , George Ellis , William Stoeger

Since this is a meeting on inflation the title of this talk should probably have been ``The cosmos as a lab for inflation''. I will illustrate how, by combining WMAP observations of the cosmic microwave background (CMB) with smaller scales…

天体物理学 · 物理学 2007-05-23 Licia verde

Angular power spectrum of the cosmic microwave background (CMB) temperature anisotropies is one of the most important on characteristics of the Universe such as its geometry and total density. Using flat sky approximation and Fourier…

宇宙学与河外天体物理 · 物理学 2015-05-30 Lung-Yih Chiang , Fei-Fan Chen

The recent three-year WMAP data have confirmed the anomaly concerning the low quadrupole amplitude compared to the best-fit \Lambda CDM prediction. We show that, allowing the large-scale spatial geometry of our universe to be…

天体物理学 · 物理学 2008-12-18 L. Campanelli , P. Cea , L. Tedesco

In a landscape of compactifications with different numbers of macroscopic dimensions, it is possible that our universe has nucleated from a vacuum where some of our four large dimensions were compact while other, now compact, directions…

高能物理 - 理论 · 物理学 2012-01-11 Julian Adamek , David Campo , Jens C. Niemeyer

Inter alia, the high precision WMAP data on Cosmic Microwave Background Radiation marginally indicate that the universe has positively curved (and hence spherical) spatial sections. In this paper, we take this data seriously and consider…

天体物理学 · 物理学 2009-11-07 Jean-Philippe Uzan , Ulrich Kirchner , George F. R. Ellis

The WMAP satellite has completed 3 years of observations of the cosmic microwave background radiation. The 3-year data products include several sets of full sky maps of the Stokes I, Q and U parameters in 5 frequency bands, spanning 23 to…

We investigate anomalies reported in the Cosmic Microwave Background maps from the Wilkinson Microwave Anisotropy Probe (WMAP) satellite on very large angular scales and discuss possible interpretations. Three independent anomalies involve…

天体物理学 · 物理学 2009-07-09 Angelica de Oliveira-Costa , Max Tegmark , Matias Zaldarriaga , Andrew Hamilton

Geometry of the universe has always intrigued mathematicians and cosmologists. Recent results from the Wilkinson Microwave Anisotropy Project (WMAP) indicate that the visible universe is incredibly flat. This apparent flatness could be due…

广义相对论与量子宇宙学 · 物理学 2013-09-24 Selcuk S. Bayin

Recent cosmic microwave background data in temperature and polarization have reached high precision in estimating all the parameters that describe the current so-called standard cosmological model. Recent results about the integrated…

The Microwave Anisotropy Probe (MAP) and Planck Surveyor satellites promise to provide accurate maps of the sky at a range of frequencies and angular scales, from which it will be possible to extract estimates for cosmological parameters.…

天体物理学 · 物理学 2007-05-23 Douglas Scott