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The properties of the cosmic microwave background (CMB) temperature and polarisation anisotropies measured by a static, off-centered observer located in a local spherically symmetric void, are described. In particular in this paper we…

宇宙学与河外天体物理 · 物理学 2017-03-22 Giulia Cusin , Cyril Pitrou , Jean-Philippe Uzan

The measurements of CMB anisotropy have opened up a window for probing the global topology of the universe on length scales comparable to and beyond the Hubble radius. For compact topologies, the two main effects on the CMB are: (1) the…

天体物理学 · 物理学 2011-04-15 J. Richard Bond , Dmitri Pogosyan , Tarun Souradeep

In this paper, we present compelling evidence for the parity asymmetry (a discrete symmetry that is separate from isotropy) in the Cosmic Microwave Background (CMB) map, measured through two-point temperature correlations. This parity…

宇宙学与河外天体物理 · 物理学 2024-06-07 Enrique Gaztañaga , K. Sravan Kumar

We review the theory of the temperature anisotropy and polarization of the cosmic microwave background (CMB) radiation, and describe what we have learned from current CMB observations. In particular, we discuss how the CMB is being used to…

宇宙学与河外天体物理 · 物理学 2010-02-22 Anthony Challinor , Hiranya Peiris

We report on the results from two independent but complementary statistical analyses of the WMAP first-year data, based on the power spectrum and N-point correlation functions. We focus on large and intermediate scales (larger than about 3…

天体物理学 · 物理学 2009-11-10 H. K. Eriksen , F. K. Hansen , A. J. Banday , K. M. Gorski , P. B. Lilje

In the standard cosmological model, the temperature anisotropy of the cosmic microwave background is interpreted as variation in the gravitational potential at the point of emission, due to the emitter being embedded in a region ${\cal C}$…

天体物理学 · 物理学 2007-05-23 Richard Lieu

We introduce a class of models in which statistical isotropy is broken spontaneously in the CMB by a non-linear response to long-wavelength fluctuations in a mediating field. These fluctuations appear as a gradient locally and pick out a…

天体物理学 · 物理学 2008-11-26 Christopher Gordon , Wayne Hu , Dragan Huterer , Tom Crawford

We discuss the time dependence and future of the Cosmic Microwave Background (CMB) in the context of the standard cosmological model, in which we are now entering a state of endless accelerated expansion. The mean temperature will simply…

天体物理学 · 物理学 2008-11-26 J. P. Zibin , A. Moss , D. Scott

Recent Wilkinson Microwave Anisotropy Probe (WMAP) data confirm the Cosmic Microwave Background (CMB) quadrupole anomaly. We further elaborate our previous proposal that the quadrupole power can be naturally suppressed in axis-symmetric…

天体物理学 · 物理学 2008-11-26 L. Campanelli , P. Cea , L. Tedesco

Cosmic microwave background measurements show an agreement with the concordance cosmology model except for a few notable anomalies: Power Suppression, the lack of large scale power in the temperature data compared to what is expected in the…

宇宙学与河外天体物理 · 物理学 2019-08-20 Shabbir Shaikh , Suvodip Mukherjee , Santanu Das , Benjamin D. Wandelt , Tarun Souradeep

We compute the CMB anisotropy in an open inflation CDM model which is normalized to the two-year DMR sky map. Presently available CMB data is consistent with $\Omega_0 \sim 0.3 - 0.4$, but does not strongly disfavour either $\Omega_0 \sim…

天体物理学 · 物理学 2009-10-28 Bharat Ratra , Anthony J. Banday , Krzysztof M. Gorski , Naoshi Sugiyama

We develop a formalism for calculating cosmic microwave background (CMB) temperature and polarization anisotropies in cosmological models with Brans-Dicke gravity. We then modify publicly available Boltzmann codes to calculate numerically…

天体物理学 · 物理学 2008-11-26 Xuelei Chen , Marc Kamionkowski

The fine-structure constant, $\alpha$, controls the strength of the electromagnetic interaction. There are extensions of the standard model in which $\alpha$ is dynamical on cosmological length and time-scales. The physics of the cosmic…

宇宙学与河外天体物理 · 物理学 2019-02-27 Tristan L. Smith , Daniel Grin , David Robinson , Davy Qi

We report measurements of the temperature dependent anisotropies ($\gamma_\lambda$ and $\gamma_\xi$) of both the London penetration depth $\lambda$ and the upper critical field of MgB$_2$. Data for $\gamma_\lambda=\lambda_c/\lambda_a$ was…

超导电性 · 物理学 2009-11-11 J. D. Fletcher , A. Carrington , O. J. Taylor , S. M. Kazakov , J. Karpinski

The anisotropy gamma of the superconducting state of high quality single-crystals of MgB2 was determined, using torque magnetometry with two different methods. The anisotropy of the upper critical field was found to be temperature…

超导电性 · 物理学 2008-11-28 M. Angst , R. Puzniak , A. Wisniewski , J. Jun , S. M. Kazakov , J. Karpinski , J. Roos , H. Keller

We study the anisotropy of the cosmic microwave background (CMB) in cold and mixed dark matter (CDM and MDM) models, with non scale-invariant primordial power spectra (i.e. $n \neq 1$) and a late, sudden reionization of the intergalactic…

We discuss selected large-scale anomalies in the maps of temperature anisotropies in the cosmic microwave background. Specfically, these include alignments of the largest modes of CMB anisotropy with one another and with the geometry and…

宇宙学与河外天体物理 · 物理学 2012-01-13 Glenn D. Starkman , Craig J. Copi , Dragan Huterer , Dominik Schwarz

Cosmological inhomogeneities gravitationally deflect radiation propagating from distant sources, transforming the spatial and angular correlation functions of intrinsic source properties. For a gaussian distribution of deflections (e.g.…

天体物理学 · 物理学 2007-05-23 Eric V. Linder

These lecture notes form a primer on the theory of cosmic microwave background (CMB) anisotropy formation. With emphasis on conceptual aspects rather than technical issues, we examine the physical foundations of anisotropy evolution in…

天体物理学 · 物理学 2015-06-24 Wayne Hu

We evaluate the angular bispectrum of the CMB temperature anisotropy at large angular scale due to a stochastic background of primordial magnetic fields. The shape of non-Gaussianity depends on the spectral index of the magnetic field power…

宇宙学与河外天体物理 · 物理学 2009-10-02 Chiara Caprini , Fabio Finelli , Daniela Paoletti , Antonio Riotto