Cosmic expansion and structure formation in running vacuum cosmologies
Abstract
We investigate the dynamics of the FriedmannLemaîtreRobertsonWalker (FLRW) flat cosmological models in which the vacuum energy varies with redshift. A particularly wellmotivated model of this type is the socalled quantum field vacuum, in which both kind of terms H2 and constant appear in the effective dark energy (DE) density affecting the evolution of the main cosmological functions at the background and perturbation levels. Specifically, it turns out that the functional form of the quantum vacuum endows the vacuum energy of a mild dynamical evolution which could be observed nowadays and appears as dynamical DE. Interestingly, the lowenergy behavior is very close to the usual Lambda cold dark matter (ΛCDM) model, but it is by no means identical. Finally, within the framework of the quantum field vacuum we generalize the large scale structure properties, namely growth of matter perturbations, cluster number counts and spherical collapse model.
 Publication:

Modern Physics Letters A
 Pub Date:
 June 2015
 DOI:
 10.1142/S0217732315400313
 arXiv:
 arXiv:1501.03749
 Bibcode:
 2015MPLA...3040031B
 Keywords:

 Cosmology;
 dark energy;
 large scale structure;
 98.80.k;
 95.35.+d;
 95.36.+x;
 Cosmology;
 Dark matter;
 Dark energy;
 Astrophysics  Cosmology and Nongalactic Astrophysics;
 General Relativity and Quantum Cosmology;
 High Energy Physics  Phenomenology;
 High Energy Physics  Theory
 EPrint:
 16 pages, 2 figures Invited paper for the Special Issue: "Fundamental Constants in Physics and Their Time Variation" (Modern Physics Letters A, Guest Editor Joan Sol\`a)