Running vacuum in the universe: Current phenomenological status

Abstract

I review the excellent phenomenological status of a class of dynamical vac- uum models in which the vacuum energy density, �� = ��(H), as a function of the Hubble rate, evolves through its interaction with dark matter and/or through the ac- companying running of the gravitational coupling G, including the possibility of being self-conserved with a nontrivial effective equation of state. Some of these models have been used to incorporate into a single vacuum structure the rapid stage of inflation, followed by the standard radiation and cold dark matter epochs all the way down until the dark energy era. Remarkably, the running vacuum models (RVM's) render an out- standing phenomenological description of the main cosmological data at a level that is currently challenging the concordanceCDM model, thereby implying that present observations seem to point to a running vacuum rather than to a rigid cosmological constantin our Universe.