Fundamental Implications of Intergalactic Magnetic Field Observations

Abstract

Helical intergalactic magnetic fields at the $\sim 10^{-14}\mathrm{G}$ level on $\sim 10\mathrm{Mpc}$ length scales are indicated by current gamma ray observations. The existence of magnetic fields in cosmic voids and their non-trivial helicity suggest that they must have originated in the early universe and thus have implications for the fundamental interactions. I combine present knowledge of the observational constraints and the dynamics of cosmological magnetic fields to derive characteristics that would need to be explained by the magnetic field generation mechanism. The importance of CP violation and a possible crucial role for chiral effects in the early universe are pointed out.

6 pages; updated references, added clarifying remarks

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Cited by in corpus (3)

• Baryogenesis from Decaying Magnetic Helicity
• Evolution of hydromagnetic turbulence from the electroweak phase transition
• Influence of the turbulent motion on the chiral magnetic effect in the early Universe