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arXiv · 2010.05927

Robustness of the Cosmological Constant Damping Mechanism Through Matter Eras

Oleg Evnin·Victor Massart·Kevin Nguyen
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Abstract

A dynamical resolution to the cosmological constant fine-tuning problem has been previously put forward, based on a scalar-tensor gravitational theory possessing de Sitter attractor solutions characterized by a small Hubble expansion rate, irrespective of an initially large vacuum energy. We show that a technically natural subregion of the parameter space yields a cosmological evolution through radiation- and matter-dominated eras that is essentially indistinguishable from that predicted by General Relativity. Similarly, the proposed model automatically satisfies the observational constraints on a fifth force mediated by the new scalar degree of freedom.

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Oleg Evnin, Victor Massart, Kevin Nguyen. 2020-10-12. Robustness of the Cosmological Constant Damping Mechanism Through Matter Eras. https://doi.org/10.1088/1361-6382%2Fac1851

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