Related papers: Dynamical Generation of the Primordial Magnetic Fi…
We show that coherent magnetic field is generated spontaneously when a large domain wall is created in the early universe. It is caused by two dimensional massless fermions bounded to the domain wall soliton. We point out that the magnetic…
In this paper we discuss once more the zero mode contribution to the vacuum energy density. We show that a careful treatment of the zero modes leads to the conclusion that domain walls may be ferromagnetic, and could generate a magnetic…
In this work we investigate the possibility of generation of primordial magnetic field in the early universe near the QCD phase transition epoch via the collapse of $Z(3)$ domains. The $Z(3)$ domain walls arise in the deconfined phase of…
We discuss a new mechanism which allows domain walls produced during the primordial electroweak phase transition. We show that the effective surface tension of these domain walls can be made vanishingly small due to a peculiar magnetic…
The generation of primordial magnetic fields from cosmological phase transitions is discussed, paying particular attention to the electroweak transition and to the various definitions of the `average' field that have been put forward. It is…
Magnetic fields appear to be present in all galaxies and galaxy clusters. Recent measurements indicate that a weak magnetic field may be present even in the smooth low density intergalactic medium. One explanation for these observations is…
It is pointed out that, contrary to some claims in the literature, the domain walls cannot be a source of a correlated at large scales primordial magnetic field, even if the fermionic modes bound on the wall had ferromagnetic properties. In…
We comment on the recent preprint hep-ph/0007123 by M.B. Voloshin, claiming that domain walls are diamagnetic. We show that the results presented therein are based on an incorrect treatment of the zero mode contribution to the vacuum energy…
It is shown that contrary to a recent claim in the literature, the domain walls made of scalar field are diamagnetic due to presence of massless fermionic modes on the wall. The diamagnetism vanishes at high temperature. Thus the domain…
We give an improved estimate of primordial magnetic fields generated during cosmological first order phase transitions. We examine the charge distribution at the nucleated bubble wall and its dynamics. We consider instabilities on the…
The explanation of the observed galactic magnetic fields may require the existence of a primordial magnetic field. Such a field may arise during the early cosmological phase transitions, or because of other particle physics related…
We present a mechanism for generating primordial magnetic fields with large correlation lengths on the order of 100 kpc today. The mechanism is based on recently conjectured QCD domain walls or similar CP violating domain walls with QCD…
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…
We show that axion domain wall is ferromagnetic in the universe with nonvanishing baryon number or lepton number. It is caused by protons and electrons bounded to the domain wall with their spins aligned. These bound states arise due to…
The response to a magnetic flux is considered of the vacuum state of charged Dirac fermions interacting with a domain wall made of a neutral spinless field in (3+1) dimensions with the fermion mass having a phase variation across the wall.…
Observations of $\gamma$-ray from blazars suggest the presence of magnetic fields in the intergalactic medium, which may require a primordial origin. Intense enough primordial magnetic fields can arise from theories of dynamical electroweak…
It is demonstrated that strong magnetic fields are produced from a zero initial magnetic field during the pregalactic era, when galaxies are first forming. Their development proceeds in three phases. In the first phase, weak magnetic fields…
An antiferromagnetic domain wall in a thermal gradient is found to experience a force towards colder regions upon the application of a uniform magnetic field along the easy axis. This force increases with the strength of the applied field…
We show that a chiral nonlinear sigma model coupled to degenerate neutrons exhibits a ferromagnetic phase at high density. The magnetization is due to the axial anomaly acting on the parallel layers of neutral pion domain walls…
A rigorous theory for the generation of a large-scale magnetic field by random non-helically forced motions of a conducting fluid combined with a linear shear is presented in the analytically tractable limit of low Rm and weak shear. The…