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Related papers: Microwave Background Signals from Tangled Magnetic…

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An inhomogeneous cosmological magnetic field creates vortical perturbations that survive Silk damping on much smaller scales than compressional modes. This ensures that there is no sharp cut-off in anisotropy on arc-minute scales. As we had…

Astrophysics · Physics 2009-11-07 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 =…

Astrophysics · Physics 2009-10-31 T. R. Seshadri , Kandaswamy Subramanian

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…

Astrophysics · Physics 2016-08-30 R. Durrer , P. G. Ferreira , T. Kahniashvili

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…

Astrophysics · Physics 2008-11-26 Andrew Mack , Tina Kahniashvili , Arthur Kosowsky

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…

Astrophysics · Physics 2008-11-26 Gang Chen , Pia Mukherjee , Tina Kahniashvili , Bharat Ratra , Yun Wang

We investigate microwave background anisotropies in the presence of primordial magnetic fields. We show that a homogeneous field with fixed direction can amplify vector perturbations. We calculate the correlations of $\delta T/T$ explicitly…

Astrophysics · Physics 2009-10-30 Ruth Durrer , Tina Kahniashvili , Andrew Yates

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…

Astrophysics · Physics 2009-11-11 Kandaswamy Subramanian

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…

Astrophysics · Physics 2009-11-07 Kandaswamy Subramanian , T. R. Seshadri , John. D. Barrow

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…

Cosmology and Nongalactic Astrophysics · Physics 2009-10-02 Chiara Caprini , Fabio Finelli , Daniela Paoletti , Antonio Riotto

The evolution and viscous damping of cosmic magnetic fields in the early universe, is analysed. Using the fact that the fluid, electromagnetic, and shear viscous energy-momentum tensors are all conformally invariant, the evolution is…

Astrophysics · Physics 2011-09-29 Kandaswamy Subramanian , John D. Barrow

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…

Astrophysics · Physics 2016-08-30 T. R. Seshadri , Kandaswamy Subramanian

The existence of large-scale anisotropy can not be ruled out by the cosmic microwave background (CMB) radiation. Over the years, several models have been proposed in the context of anisotropic inflation to account for CMB's cold spot and…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-15 Sourav Pal , Debaprasad Maity , Tuan Q. Do

In the presence of the primordial magnetic field, initial vector (vorticity) perturbations produce cosmological Alfven waves and leave imprints on cosmic microwave background (CMB) temperature and polarization anisotropy. We have…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-18 Jaiseung Kim , Pavel Naselsky

The arrival directions of multi-TeV cosmic rays show significant anisotropies at small angular scales. It has been argued that this small scale structure is reflecting the local, turbulent magnetic field in the presence of a global dipole…

High Energy Astrophysical Phenomena · Physics 2015-12-01 Philipp Mertsch , Markus Ahlers

The theoretical basis for the prediction of anisotropies in the cosmic microwave background is very well developed. Very low amplitude density and temperature perturbations produce small gravitational effects, leading to an anisotropy that…

Astrophysics · Physics 2007-05-23 E. L. Wright

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.…

Cosmology and Nongalactic Astrophysics · Physics 2011-06-10 Maresuke Shiraishi , Daisuke Nitta , Shuichiro Yokoyama , Kiyotomo Ichiki , Keitaro Takahashi

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 ${\cal C}$…

Astrophysics · Physics 2007-05-23 Richard Lieu

Prior to photon decoupling magnetic random fields of comoving intensity in the nano-Gauss range distort the temperature and the polarization anisotropies of the microwave background, potentially induce a peculiar B-mode power spectrum and…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-04 Massimo Giovannini

The solar wind and the interstellar medium are permeated by large-scale magnetic fields that render magnetohydrodynamic (MHD) turbulence anisotropic. In the weak-turbulence limit in which three-wave interactions dominate, analytical and…

Solar and Stellar Astrophysics · Physics 2011-09-06 C. S. Ng , A. Bhattacharjee

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…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-19 Karsten Jedamzik , Tom Abel
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