Speaker
Christof Wetterich
Description
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.
This is a possible solution of the "why now" problem.
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. A simple and realistic dark energy cosmology can be
obtained in this way.
