Kinematic fast cosmic dynamos in non-inflationary phases of ellipsoidal universe

TL;DR

This paper demonstrates the existence of cosmic kinematic fast dynamos in non-inflationary phases of an ellipsoidal universe, showing magnetic field amplification via a Zeldovich STF mechanism, contrasting with decay during inflation.

Contribution

It introduces a new model of cosmic dynamo action in non-inflationary ellipsoidal universes, highlighting the conditions for magnetic field amplification and decay.

Findings

Magnetic fields are amplified in non-inflationary phases.

Dynamo action is absent during inflation, leading to magnetic field decay.

The model aligns with Zeldovich's STF dynamo mechanism.

Abstract

Cosmic kinematic fast dynamo is found in non-inflationary phases of an ellipsoidal anisotropic cosmological metric background solution of Einstein field equations of general relativity. The magnetic field is amplified inside the universe and spatially periodically. A finite resistivity is assumed, and a nonsingular flow velocity is aligned with the magnetic field which is orthogonal to a plane which is analog to a galactic plane in astrophysics. Magnetic field components is stretched along the z-direction and a cosmic dynamo is created in the spirit of Zeldovich stretch, twist and fold (STF) dynamo generation mechanism. In the inflationary phase of the planar symmetric universe, the primordial magnetic field decays and the galactic plane expands as a de Sitter $(2+1)-spacetime$ and the eccentricity of the ellipsoidal universe, tends to vanish with inflation. We may conclude that, as far as the present model is concerned, anti-dynamos are obtained in inflationary phases.