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arXiv · 0801.4526

Pseudo-redundant vacuum energy

Puneet Batra·Kurt Hinterbichler·Lam Hui·Daniel Kabat
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Abstract

We discuss models that can account for today's dark energy. The underlying cosmological constant may be Planck scale but starts as a redundant coupling which can be eliminated by a field redefinition. The observed vacuum energy arises when the redundancy is explicitly broken, say by a non-minimal coupling to curvature. We give a recipe for constructing models, including R + 1/R type models, that realize this mechanism and satisfy all solar system constraints on gravity. A similar model, based on Gauss-Bonnet gravity, provides a technically natural explanation for dark energy and exhibits an interesting see-saw behavior: a large underlying cosmological constant gives rise to both low and high curvature solutions. Such models could be statistically favored in the string landscape.

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Puneet Batra, Kurt Hinterbichler, Lam Hui, Daniel Kabat. 2008-08-26. Pseudo-redundant vacuum energy. https://doi.org/10.1103/physrevd.78.043507

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