Hubble expansion and structure formation in the "running FLRW model" of the cosmic evolution
arXiv:1103.4632 · doi:10.1088/1475-7516/2011/08/007
Abstract
A new class of FLRW cosmological models with time-evolving fundamental parameters should emerge naturally from a description of the expansion of the universe based on the first principles of quantum field theory and string theory. Within this general paradigm, one expects that both the gravitational Newton's coupling, G, and the cosmological term, Lambda, should not be strictly constant but appear rather as smooth functions of the Hubble rate. This scenario ("running FLRW model") predicts, in a natural way, the existence of dynamical dark energy without invoking the participation of extraneous scalar fields. In this paper, we perform a detailed study of these models in the light of the latest cosmological data, which serves to illustrate the phenomenological viability of the new dark energy paradigm as a serious alternative to the traditional scalar field approaches. By performing a joint likelihood analysis of the recent SNIa data, the CMB shift parameter, and the BAOs traced by the Sloan Digital Sky Survey, we put tight constraints on the main cosmological parameters. Furthermore, we derive the theoretically predicted dark-matter halo mass function and the corresponding redshift distribution of cluster-size halos for the "running" models studied. Despite the fact that these models closely reproduce the standard LCDM Hubble expansion, their normalization of the perturbation's power-spectrum varies, imposing, in many cases, a significantly different cluster-size halo redshift distribution. This fact indicates that it should be relatively easy to distinguish between the "running" models and the LCDM cosmology using realistic future X-ray and Sunyaev-Zeldovich cluster surveys.
Version published in JCAP 08 (2011) 007: 1+41 pages, 6 Figures, 1 Table. Typos corrected. Extended discussion on the computation of the linearly extrapolated density threshold above which structures collapse in time-varying vacuum models. One appendix, a few references and one figure added
References in corpus (33)
- Wilkinson Microwave Anisotropy Probe (WMAP) Three Year Results: Implications for Cosmology
- Dynamics of dark energy
- Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Interpretation
- Improved Cosmological Constraints from New, Old and Combined Supernova Datasets
- Improved Dark Energy Constraints from ~100 New CfA Supernova Type Ia Light Curves
- The halo mass function from the dark ages through the present day
- Dark energy: a quantum fossil from the inflationary Universe?
- Holographic dark energy with varying gravitational constant
- Structure formation in the presence of dark energy perturbations
- Clustering of luminous red galaxies I: large scale redshift space distortions
- Probing polarization states of primordial gravitational waves with CMB anisotropies
- LXCDM: a cosmon model solution to the cosmological coincidence problem?
- Dynamic vacuum variable and equilibrium approach in cosmology
- Zero-point quantum fluctuations and dark energy
- Confronting Dark Energy Models using Galaxy Cluster Number Counts
- The spherical collapse model and cluster formation beyond the cosmology: Indications for a clustered dark energy?
- Testing Cosmology with Cosmic Sound Waves
- Dynamically avoiding fine-tuning the cosmological constant: the "Relaxed Universe"
- Relaxing a large cosmological constant
- Virialization of cosmological structures in models with time varying equation of state
- The solution of the cosmological constant problem from the inhomogeneous equation of state - a hint from modified gravity?
- Evolution of density perturbations in decaying vacuum cosmology: The case of non-zero perturbations in the cosmological term
- Effective growth of matter density fluctuations in the running LCDM and LXCDM models
- Can the cosmological "constant" run? - It may run
- Vacuum fluctuations in a supersymmetric model in FRW spacetime
- Planck Scale Cosmology in Resummed Quantum Gravity
- Pseudo-redundant vacuum energy
- New mechanism to cross the phantom divide
- Cosmologies with variable parameters and dynamical cosmon: implications on the cosmic coincidence problem
- The cosmological constant and the relaxed universe
- The Cosmological Constant and Discrete Space-Times
- Resummed Quantum Gravity
- What is there in the black box of dark energy: variable cosmological parameters or multiple (interacting) components?