Evidence for Strong Intracluster Magnetic Fields in the Early Universe

Magnetic Fields in the Early Universe

We discuss some old and new results on mangetic fields

Magnetic Fields in the Early Universe

The observed galactic magnetic fields may have a primordial origin. I briefly review the observations, their interpretation in terms of the dynamo theory, and the current limits on cosmological magnetic fields. Several possible mechanisms for generating a primordial magnetic field are then discussed. Turbulence and the evolution of the microscopic fields to macroscopic fields is described in te...

On the evolution of magnetic fields in the early universe

We address the question of the existence of magnetic domains in a recent scenario for the creation of primordial magnetic fields. We write down the magnetohydrodynamic equation in an expanding universe in the infinite conductivity limit and discuss its solution. No domains are found. [email protected]; [email protected] We have recently presented a scenario for the creation of a primord...

Evolution of primordial magnetic fields in the early universe

Decay of Magnetic Fields in the Early Universe∗

We study the evolution of a stochastic helical magnetic field generated in the early Universe after the electroweak phase transition, using standard magnetohydrodynamics (MHD). We find how the coherence length ξ, magnetic energy EM and magnetic helicity H evolve with time. We show that the self-similarity of the magnetic power spectrum alone implies that ξ ∼ t1/2. This in turn implies that magn...