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Extended quintessence and the primordial helium abundance

Xuelei Chen·Robert J. Scherrer·Gary Steigman
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Abstract

In extended quintessence models, a scalar field which couples to the curvature scalar R provides most of the energy density of the universe. We point out that such models can also lead naturally to a decrease in the primordial abundance of helium-4, relieving the tension which currently exists between the primordial helium-4 abundance inferred from observations and the amount predicted by Standard Big Bang Nucleosynthesis (SBBN) corresponding to the observed deuterium abundance. Using negative power-law potentials for the quintessence field, we determine the range of model parameters which can lead to an interesting reduction in the helium-4 abundance, and we show that it overlaps with the region allowed by other constraints on extended quintessence models.

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Xuelei Chen, Robert J. Scherrer, Gary Steigman. 2001-06-21. Extended quintessence and the primordial helium abundance. https://doi.org/10.1103/physrevd.63.123504

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