Primordial Magnetic Fields from Cosmological First Order Phase Transitions
نویسندگان
چکیده
We give an improved estimate of primordial magnetic elds generated during cosmological rst order phase transitions. We examine the charge distribution at the nucleated bubble wall and its dynamics. We consider instabilities on the bubble walls developing during the phase transition. It is found that damping of these instabilities due to viscosity and heat conductivity caused by particle di usion can be important in the QCD phase transition, but is probably negligible in the electroweak transition. We show how such instabilities together with the surface charge densities on bubble walls excite magnetic elds within a certain range of wavelengths. We discuss how these magnetic seed elds may be ampli ed by MHD e ects in the turbulent uid. The strength and spectrum of the primordial magnetic eld at the present time for the cases where this mechanism was operative during the electroweak or the QCD phase transition are estimated. On a 10Mpc comoving scale, eld strengths of the order 10 G for electroweak and 10 20 G for QCD, could be attained for reasonable phase transition parameters.
منابع مشابه
The Stability of Primordial Magnetic Fields Produced by Phase Transitions
Primordial magnetic fields seem to be a generic relic of phase transitions in the early universe. We consider a primordial electromagnetic field formed as a result of a second-order phase transition, and show that it is stable to thermal fluctuations in the period immediately following. We also show how such a field arises in first order phase transitions. In both cases there is a transitive el...
متن کاملPrimordial Magnetic Fields
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 phenomena in the very early universe reviewed here. The turbulent evolution of the initial, randomly fluctuating microscopic field to a large-scale macroscopic field...
متن کاملCosmological Symmetry Breaking and Generation of Electromagnetic Field
Cosmological phase transitions accompanied by some kind of symmetry breaking would cause the creation of topological defects and the resulting production of primordial magnetic field. Moreover, such a procedure inevitably affects the cosmic background radiation and it may be observed today. Motivated by the existence of stabilized embedded defects in the standard model of elementary interaction...
متن کاملMagnetic Fields from Bubble Collisions — A Progress Report
Primordial magnetic fields may be created in collisions of expanding bubbles in a first-order cosmological phase transition and later serve as seed fields for galactic magnetic fields. Here I present results from numerical and analytical studies of U(1) bubble collisions done in collaboration with Ed Copeland and Paul Saffin. I also reveal preliminary results from analytical studies of SU(2)×U(...
متن کاملMagnetic field generation from non-equilibrium phase transitions
We study the generation of magnetic fields during the stage of particle production resulting from spinodal instabilities during phase transitions out of equilibrium. The main premise is that long-wavelength instabilities that drive the phase transition lead to strong non-equilibrium charge and current fluctuations which generate electromagnetic fields. We present a formulation based on the non-...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 1996