Magnetic Fields in the Early Universe

Cosmological Magnetic Fields

We discuss the evolution of cosmological magnetic fields from the early universe to the present. We review different scenarios for magnetogenesis in the early universe and follow the subsequent evolution of these fields as the universe recombines. We then focus on the role primordial fields play after recombination in the seeding of stellar and galactic fields and the formation of structure. Co...

میدانهای مغناطیسی بزرگ مقیاس و جفت‌شدگیهای الکترو- دیلاتونی و خمش

 We investigate the generation of large scale magnetic fields in the universe from quantum fluctuations that are produced in the inflationary stage. By coupling these quantum fluctuations to the dilaton field and Ricci scalar, we show that the magnetic fields with the strength observed today can be produced. We consider two situations. First, the evolution of dilaton ends by starting the reheat...

The origin of cosmic magnetic fields ∗

In this talk, I review a number of particle-physics models that lead to the creation of magnetic fields in the early universe and address the complex problem of evolving such primordial magnetic fields into the fields observed today. Implications for future observations of the Cosmic Microwave Background (CMB) are discussed. Focussing on first-order phase transitions in the early universe, I de...

Plasma magnetization by a nonuniform electromagnetic beam

I. Introduction Understanding the origin of magnetic fields in cosmic and laser produced plasmas has been of great theoretical as well as experimental interest [1–3]. The generation of seed magnetic fields in the early universe is a long-standing mystery in astrophysics. A very weak magnetic field (typically of the order of one to thirty microgauss) in the early universe has been of much intere...

Evolution of primordial magnetic fields in the early universe

Cosmological Structure Formation Creates Large-scale Magnetic Fields

This paper examines the generation of seed magnetic fields due to the growth of cosmological perturbations. In the radiation era, different rates of scattering from photons induce local differences in the ion and electron density and velocity fields. The currents due to the relative motion of these fluids generate magnetic fields on all cosmological scales, peaking at a magnitude of O(10 G) at ...