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arXiv · 1902.06793

Relaxation of the Cosmological Constant

Peter W. Graham·David E. Kaplan·Surjeet Rajendran
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Abstract

We present a model that naturally tunes a large positive cosmological constant to a small cosmological constant. A slowly rolling scalar field decreases the cosmological constant to a small negative value, causing the universe to contract, thus reheating it. An expanding universe with a small positive cosmological constant can be obtained, respectively, by coupling this solution to any model of a cosmological bounce and coupling the scalar field to a sector that undergoes a technically natural phase transition at the meV scale. A robust prediction of this model is a rolling scalar field today with some coupling to the standard model. This can potentially be experimentally probed in a variety of cosmological and terrestrial experiments, such as probes of the equation of state of dark energy, birefringence in the cosmic microwave background and terrestrial tests of Lorentz violation.

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Peter W. Graham, David E. Kaplan, Surjeet Rajendran. 2019-02-18. Relaxation of the Cosmological Constant. https://doi.org/10.1103/physrevd.100.015048

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