Cosmological Bounces Induced by a Fermion Condensate

Abstract

We show that it is possible for fermion condensation of the Nambu-Jona-Lasinio type to induce a non-singular bounce that smoothly connects a phase of slow contraction to a phase of expansion. A chiral condensate -- a non-zero vacuum expectation value of the spinor bilinear $⟨\bar{\Psi }\Psi ⟩$ -- can form spontaneously after a slow contraction phase smooths and flattens the universe and the Ricci-curvature exceeds a critical value. In this approach, a high density of spin-aligned free fermions is not required, which avoids the problem of generating a large anisotropy and initiating chaotic mixmaster behavior during the bounce phase.

5 pages, 4 figures; to appear in PRL

References in corpus (3)

• Supersmoothing through Slow Contraction
• The cosmological BCS mechanism and the Big Bang Singularity
• Robustness of slow contraction to cosmic initial conditions

Cited by in corpus (8)

• Cold Dark Matter Based on an Analogy with Superconductivity
• Bispectrum Islands
• A short review on Quintom dark energy theory
• Tunnelling-induced cosmic bounce in the presence of anisotropies
• Torsion, Gravity Induced Chiral Symmetry Breaking and Cosmological Bounce
• Probability of the Initial Conditions for Inflation and Slow Contraction
• Covariant single-field formulation of effective cosmological bounces
• Fermionic quantum cosmology as a framework for resolving type IV singularities