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Tangled, primordial cosmic magnetic fields create small rotational velocity perturbations on the last scattering surface (LSS) of the cosmic microwave background radiation (CMBR). Such perturbations can contribute significantly to the CMBR…

天体物理学 · 物理学 2009-11-07 Kandaswamy Subramanian , T. R. Seshadri , John. D. Barrow

An inhomogeneous cosmological magnetic field will create Alfven-wave modes that induce a small rotational velocity perturbation on the last scattering surface of the microwave background radiation. The Alfven-wave mode survives Silk damping…

天体物理学 · 物理学 2011-05-05 Kandaswamy Subramanian , John D. Barrow

Tangled, primordial cosmic magnetic fields create small rotational velocity perturbations on the last scattering surface (LSS) of the cosmic microwave background radiation (CMBR). For fields which redshift to a present value of $B_0 =…

天体物理学 · 物理学 2009-10-31 T. R. Seshadri , Kandaswamy Subramanian

Possible signatures of primordial magnetic fields on the Cosmic Microwave Background (CMB) temperature and polarization anisotropies are reviewed. The signals that could be searched for include excess temperature anisotropies particularly…

天体物理学 · 物理学 2009-11-11 Kandaswamy Subramanian

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

Primordial tangled cosmological Magnetic Fields source rotational velocity perturbations of the baryon fluid, even in the post-recombination universe. These vortical modes inturn leave a characteristic imprint on the temperature anisotropy…

天体物理学 · 物理学 2016-08-30 T. R. Seshadri , Kandaswamy Subramanian

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

A stochastic magnetic field in the early Universe will produce anisotropies in the temperature and polarization of the cosmic microwave background. We derive analytic expressions for the microwave background temperature and polarization…

天体物理学 · 物理学 2008-11-26 Andrew Mack , Tina Kahniashvili , Arthur Kosowsky

Recent observations of the cosmic microwave background (CMB) have extended the measured power spectrum to higher multipoles $l\gtrsim$1000, and there appears to be possible evidence for excess power on small angular scales. The primordial…

天体物理学 · 物理学 2009-02-19 D. Yamazaki , K. Ichiki , T. Kajino , G. J. Mathews

It is shown that small-scale magnetic fields present before recombination induce baryonic density inhomogeneities of appreciable magnitude. The presence of such inhomogeneities changes the ionization history of the Universe, which in turn…

宇宙学与河外天体物理 · 物理学 2015-03-19 Karsten Jedamzik , Tom Abel

Galactic magnetic fields are observed of order $\sim 10^{-6}G$, but their origin is not definitely known yet. In this paper we consider the primordial magnetic fields generated in the early universe and analyse their effects on the density…

天体物理学 · 物理学 2016-08-30 Seoktae Koh , Chul H. Lee

The primordial magnetic fields (PMFs) produced in the early universe are expected to be the origin of the large-scale cosmic magnetic fields. The PMFs are considered to leave a footprint on the cosmic microwave background (CMB) anisotropies…

宇宙学与河外天体物理 · 物理学 2021-05-17 Teppei Minoda , Kiyotomo Ichiki , Hiroyuki Tashiro

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

We investigate the power spectrum of the distortion of Cosmic Microwave Background (CMB) due to the decay of the primordial magnetic fields. It is known that there are two-types of the CMB distortions, so-called \mu- and y-types and we find…

宇宙学与河外天体物理 · 物理学 2014-03-12 Koichi Miyamoto , Toyokazu Sekiguchi , Hiroyuki Tashiro , Shuichiro Yokoyama

We derive an expression for the angular power spectrum of cosmic microwave background anisotropies due to gravity waves generated by a stochastic magnetic field and compare the result with current observations; we take into account the…

天体物理学 · 物理学 2016-08-30 R. Durrer , P. G. Ferreira , T. Kahniashvili

If the seed magnetic fields exist in the early Universe, tensor components of their anisotropic stresses are not compensated prior to neutrino decoupling and the tensor metric perturbations generated from them survive passively.…

宇宙学与河外天体物理 · 物理学 2011-06-10 Maresuke Shiraishi , Daisuke Nitta , Shuichiro Yokoyama , Kiyotomo Ichiki , Keitaro Takahashi

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

Primordial magnetic fields lead to non-Gaussian signals in the cosmic microwave background (CMB) even at the lowest order, as magnetic stresses and the temperature anisotropy they induce depend quadratically on the magnetic field. In…

宇宙学与河外天体物理 · 物理学 2011-01-17 Pranjal Trivedi , Kandaswamy Subramanian , T. R. Seshadri

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

We estimate the depolarizing effect of a primordial magnetic field upon the cosmic microwave background radiation due to differential Faraday rotation across the last scattering surface. The degree of linear polarization of the CMB is…

天体物理学 · 物理学 2014-10-13 Diego Harari , Justin Hayward , Matias Zaldarriaga
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