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arXiv · hep-th/0410250

Gravitational Instability of the Vacuum and the Cosmological Constant Problem

J. W. Moffat
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Abstract

A mechanism for suppressing the cosmological constant is described, using a superconducting analogy in which fermions coupled to gravitons are in an unstable false vauum. The coupling of the fermions to gravitons and a screened attractive interaction among pairs of fermions generates fermion condensates with zero momentum and a phase transition induces a non-perturbative transition to a true vacuum state. This produces a positive energy gap $Δ$ in the vacuum energy identified with $\sqrtΛ$, where $Λ$ is the cosmological constant. In the strong coupling limit, a large cosmological constant induces a period of inflation in the early universe, followed by a weak coupling limit in which $\sqrtΛ$ vanishes exponentially fast as the universe expands due to the dependence of the energy gap on the Fermi surface fermions, predicting a small cosmological constant in the early universe.

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J. W. Moffat. 2004-10-26. Gravitational Instability of the Vacuum and the Cosmological Constant Problem. https://doi.org/10.1142/s0217751x05028387

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