Ferromagnetic instability in PAAI in the sky

TL;DR

This paper proposes a theoretical model where ferromagnetic instability in an idealized plasma could explain Dark Energy and seed cosmic magnetic fields, linking micro-scale fermion properties to large-scale cosmological phenomena.

Contribution

It introduces the PAAI plasma model with asymmetric fermion masses, showing how ferromagnetic instability leads to stable domain walls that mimic Dark Energy and generate cosmic magnetic seeds.

Findings

Ferromagnetic instability creates stable domain wall complexes.

These complexes can simulate Dark Energy without evolution over cosmic time.

Residual magnetic fields can seed cosmic magnetic fields.

Abstract

We study an idealised plasma of fermions, coupled through an abelian gauge force $U(1)_X$, and which is asymmetric in that the masses of the oppositely charged species are greatly unequal. The system is dubbed PAAI, plasma asym\'etrique, ab\'elien et id\'ealis\'e. It is argued that due to the ferromagnetic instability that arises, the ground state gives rise to a complex of domain walls. This complex being held together by stresses much stronger than cosmic gravity, does not evolve with the scale factor and along with the heavier oppositely charged partners simulates the required features of Dark Energy with mass scale for the lighter fermions in the micro-eV to nano-eV range. Further, residual $X$-magnetic fields through mixture with standard magnetic fields, can provide the seed for cosmic-scale magnetic fields. Thus the scenario can explain several cosmological puzzles including Dark Energy.