2019/01/04 by R. B. MacKenzie, MacKenzie, R. B., M. B. Paranjape +3 · 1 citation
Physics and Astronomy · #Cosmology and Nongalactic Astrophysics (astro-ph.CO) #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #High Energy Physics - Theory (hep-th) #Strongly Correlated Electrons (cond-mat.str-el) #astro-ph.CO #cond-mat.str-el #hep-ph #hep-th
paper · pdf · doi:10.48550/arxiv.1901.00995
36 pages 10 figures, references and TOC added in v2
arxiv created 2019/01/17 · arxiv updated 2019/01/21
We study the physical conditions for the occurrence of ferromagnetic instability in a neutral plasma of fermions. We consider a system of two species M and Y which are oppositely charged under a local U(1)X, with M much lighter than Y. The leading correction to free quasiparticle behaviour for the lighter species arises from the exchange interaction, while the heavier species remain spectators. This plasma, which is abelian, asymmetric and idealised, is shown to be naturally susceptible to the formation of a completely spin-imbalanced ferromagnetic state for the lighter species (dubbed a magnino) in large parts of parameter space. It is shown that the domain structure formed by this ferromagnetic state can mimic Dark Energy, determining the masses of the two fermion species involved, depending on their abundance relative to the standard photons. Incomplete cancellation of the X-magnetic fields among the domains can give rise to residual long range X-magnetic fields. Under the assumption that this U(1)X mixes with Maxwell electromagnetism, this provides a mechanism for the seed for cosmic-scale magnetic fields. An extended model with several flavours Ma and Ya of the species can incorporate Dark Matter. Thus the scenario shows the potential for explaining the large scale magnetic fields, and what are arguably the two most important outstanding puzzles of cosmology: Dark Matter and Dark Energy.