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Geometrical Constraints on the Cosmological Constant

M. D. Maia·G. S. Silva
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Abstract

The cosmological constant problem is examined under the assumption that the extrinsic curvature of the space-time contributes to the vacuum. A compensation mechanism based on a variable cosmological term is proposed. Under a suitable hypothesis on the behavior of the extrinsic curvature, we find that an initially large $Λ(t)$ rolls down rapidly to zero during the early stages of the universe. Using perturbation analysis, it is shown that such vacuum behaves essentially as a spin-2 field which is independent of the metric.

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M. D. Maia, G. S. Silva. 1994-01-07. Geometrical Constraints on the Cosmological Constant. https://doi.org/10.1103/physrevd.50.7233

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