CMB temperature anisotropy at large scales induced by a causal primordial magnetic field

Details CMB temperature anisotropy at large scales induced by a causal primordial magnetic field CMB temperature anisotropy at large scales induced by a causal primordial magnetic field

2010-04-08

arxiv.org/abs/1004.1405v2

JCAP 1005:022,2010

Astronomy and Astrophysics

Astrophysics

Cosmology and Extragalactic Astrophysics

31 pages, 2 figures, minor changes, matches published version

Scientific paper

We present an analytical derivation of the Sachs Wolfe effect sourced by a primordial magnetic field. In order to consistently specify the initial conditions, we assume that the magnetic field is generated by a causal process, namely a first order phase transition in the early universe. As for the topological defects case, we apply the general relativistic junction conditions to match the perturbation variables before and after the phase transition which generates the magnetic field, in such a way that the total energy momentum tensor is conserved across the transition and Einstein's equations are satisfied. We further solve the evolution equations for the metric and fluid perturbations at large scales analytically including neutrinos, and derive the magnetic Sachs Wolfe effect. We find that the relevant contribution to the magnetic Sachs Wolfe effect comes from the metric perturbations at next-to-leading order in the large scale limit. The leading order term is in fact strongly suppressed due to the presence of free-streaming neutrinos. We derive the neutrino compensation effect dynamically and confirm that the magnetic Sachs Wolfe spectrum from a causal magnetic field behaves as l(l+1)C_l^B \propto l^2 as found in the latest numerical analyses.

Affiliated with

Also associated with

No associations

Rating

CMB temperature anisotropy at large scales induced by a causal primordial magnetic field does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with CMB temperature anisotropy at large scales induced by a causal primordial magnetic field, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and CMB temperature anisotropy at large scales induced by a causal primordial magnetic field will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-713511