2006/09/10 by Stephon Alexander, Stephon H. S. Alexander, Alexander, Stephon H. S. +2 · 2 citations
Earth and Planetary Sciences · Physics and Astronomy · #Cosmology and Gravitation Theories #FOS: Physical sciences #Geophysics and Gravity Measurements #High Energy Physics - Theory (hep-th) #Solar and Space Plasma Dynamics #hep-th
paper · pdf · doi:10.48550/arxiv.hep-th/0609066
19 pages, 1 figure
arxiv created 2006/09/10 · openalex publication_date 2006/09/10 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
It is well known that the covariant coupling of fermionic matter to gravity induces a four-fermion interaction. The presence of this term in a homogenous and isotropic space-time results in a BCS-like Hamiltonian and the formation of a chiral condensate with a mass gap. We calculate the gap (Δ) via a mean-field approximation for minimally coupled fermionic fields in a FRW background and find that it depends on the scale factor. The calculation also yields a correction to the bare cosmological constant (Λ0), and a non-zero vev for which then behaves as a scalar field. Hence we conjecture that the presence of fermionic matter in gravity provides a natural mechanism for relaxation of the Λ0 and explains the existence of a scalar field from (almost) first principles.