Growing neutrinos and cosmological selection

C. Wetterich

doi:10.1016/j.physletb.2007.08.060

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arXiv · 0706.4427

Growing neutrinos and cosmological selection

C. Wetterich

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Abstract

The time evolution of a cosmological scalar field can be stopped by an increasing mass of the neutrinos. This leads to a transition from a cosmological scaling solution with dynamical dark energy at early time to a cosmological constant dominated universe at late time. The trigger for the transition is set at the time when the neutrinos become non-relativistic. The characteristic mass scale for dark energy is thus related to the neutrino mass, the only known particle physics scale in its vicinity. This explains the ``why now problem'' for dark energy. We present a particle physics realization of this ``growing matter'' scenario. It is based on the very slowly varying mass of a superheavy scalar triplet field whose expectation value dominates the light neutrino masses.

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C. Wetterich. 2007-08-01. Growing neutrinos and cosmological selection. https://doi.org/10.1016/j.physletb.2007.08.060

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