Cosmic Magnetic Fields and the CMB
arXiv:astro-ph/0609216 · doi:10.1016/j.newar.2006.11.057
Abstract
I describe the imprint of primordial magnetic fields on the CMB. I show that these are observable only if the field amplitude is of the order of $B\gsim 10^{-9}G$ on Mpc scale. I further argue that such fields are strongly constrained by the stochastic background of gravity waves which they produce. Primordial magnetic fields, which are strong enough to be seen in the CMB, are compatible with the nucleosynthesis bound, only if their spectrum is close to scale invariant, or maybe if helical magnetic fields provoke an inverse cascade. For helical fields, the CMB signature is especially interesting. It contains parity violating T-B and E--B correlations.
12 pages, 6 figures, Contribution to the proceedings of the Francesco Melchiorri Memorial conference, Rome, April 2006
Cited by in corpus (7)
- Cosmology with inhomogeneous magnetic fields
- Magnetic field production during preheating at the electroweak scale
- CMB bispectrum from primordial magnetic fields on large angular scales
- Cosmological magnetic fields from nonlinear effects
- Possible extensions of the standard cosmological model: anisotropy, rotation, and magnetic field
- Instability of reconstruction of the low CMB multipoles
- Limits on high-frequency gravitational wave background from its interplay with large scale magnetic fields