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相关论文: CMB limits on large-scale magnetic fields in an in…

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Possible effects of large-scale magnetic fields on the Cosmic Microwave Background (CMB) are reviewed. Depending on the specific branch of the spectrum of plasma excitations, magnetic fields are treated either within a two-fluid plasma…

天体物理学 · 物理学 2009-11-13 Massimo Giovannini

Spatially fluctuating primordial magnetic fields (PMFs) inhomogeneously reheat the Universe when they dissipate deep inside the horizon before recombination. Such an energy injection turns into an additional photon temperature perturbation.…

宇宙学与河外天体物理 · 物理学 2019-11-28 Shohei Saga , Atsuhisa Ota , Hiroyuki Tashiro , Shuichiro Yokoyama

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

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

In this work we investigate the effects of the primordial magnetic fields on cosmic microwave background anisotropies (CMB). Based on cosmological magnetohydrodynamic (MHD) simulations we calculate the CMB anisotropy spectra and…

天体物理学 · 物理学 2009-11-13 Hiroyuki Tashiro , Naoshi Sugiyama , Robi Banerjee

The anisotropies of the cosmic microwave background (CMB) are computed for the half-turn space E_2 which represents a compact flat model of the Universe, i.e. one with finite volume. This model is inhomogeneous in the sense that the…

宇宙学与河外天体物理 · 物理学 2015-05-20 R. Aurich , S. Lustig

A primordial cosmological magnetic field induces and supports vorticity or Alfven waves, which in turn generate cosmic microwave background (CMB) anisotropies. A homogeneous primordial magnetic field with fixed direction induces…

天体物理学 · 物理学 2008-11-26 Gang Chen , Pia Mukherjee , Tina Kahniashvili , Bharat Ratra , Yun Wang

Large-scale magnetic fields affect the scalar modes of the geometry whose ultimate effect is to determine the anisotropies of the Cosmic Microwave Background (CMB in what follows). For the first time, a consistent numerical approach to the…

天体物理学 · 物理学 2010-04-29 Massimo Giovannini , Kerstin E. Kunze

Primordial magnetic fields present since before the epoch of matter-radiation equality have an effect on the anisotropies of the cosmic microwave background. The CMB anisotropies due to scalar perturbations are calculated in the gauge…

宇宙学与河外天体物理 · 物理学 2011-02-02 Kerstin E. Kunze

Primordial magnetic fields will generate non-Gaussian signals in the cosmic microwave background (CMB) as magnetic stresses and the temperature anisotropy they induce depend quadratically on the magnetic field. We compute a new measure of…

宇宙学与河外天体物理 · 物理学 2012-06-15 Pranjal Trivedi , T. R. Seshadri , Kandaswamy Subramanian

In recent years, there have been increasing challenges to the cosmological principle, based on new observations of e.g. supernovae and the cosmic bulk flow. As a result, the cosmological community is speaking their concern for the…

广义相对论与量子宇宙学 · 物理学 2026-05-15 Robbert W. Scholtens , Marcello Seri , Holger Waalkens , Rien van de Weygaert

The Cosmic Microwave Background Radiation (CMB) is an invaluable probe of the conditions of the early universe. Recent measurements of its spatial anisotropy have allowed accurate determinations of several fundamental cosmological…

天体物理学 · 物理学 2009-09-29 Christopher O'Dell

We have investigated the cosmic microwave background (CMB) anisotropy in closed multiply connected universes (flat and hyperbolic) with low matter density. We show that the COBE constraints on these low matter density models with…

天体物理学 · 物理学 2016-08-30 Kaiki Taro Inoue

Observers have demonstrated that it is now feasible to measure the cosmic microwave background (CMB) temperature at high redshifts. We explore the possible constraints on cosmology which might ultimately be derived from such measurements.…

天体物理学 · 物理学 2009-11-07 John M. LoSecco , Grant J. Mathews , Yun Wang

The cosmological magnetic field is one of the important physical quantities which affect strongly the cosmic microwave background (CMB) power spectrum. Recent CMB observations have been extended to higher multipoles $l\gtrsim$1000, and they…

天体物理学 · 物理学 2009-11-10 D. G. Yamazaki , K. Ichiki , T. Kajino

Cosmic microwave background (CMB) anisotropies and density fluctuations are calculated for flat cold dark matter (CDM) models with a wide range of parameters, i.e., $\Omega_0, h$ and $\Omega_B$ for both standard recombination and various…

天体物理学 · 物理学 2009-10-22 Naoshi Sugiyama

Assuming that the cosmological principle holds, Maartens, Ellis and Stoeger (MES) recently constructed a detailed scheme linking anisotropies in the cosmic background radiation (CMB) with anisotropies and inhomogeneities in the large scale…

天体物理学 · 物理学 2008-12-01 William Stoeger , Marcelo Araujo , Tim Gebbie

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

A complete numerical calculation of the temperature anisotropies and the polarization of the cosmic microwave background (CMB) is presented for a non zero cross correlation of a stochastic magnetic field with the primordial curvature…

宇宙学与河外天体物理 · 物理学 2013-05-15 Kerstin E. Kunze

In this talk, I review some recent work on cosmic microwave background (CMB) anisotropies in an open universe. I emphasize that the observed CMB anisotropies are still consistent with a low value of $\Omega$, and I address the question of…

天体物理学 · 物理学 2007-05-23 Marc Kamionkowski
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