Constraints on cold dark matter accelerating cosmologies and cluster formation

Journal Article · Thu Jul 15 04:00:00 EDT 2010 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.82.023504· OSTI ID:21410093

Basilakos, S ^[1]; Lima, J A. S. ^[2]

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1. Academy of Athens, Research Center for Astronomy and Applied Mathematics, Soranou Efesiou 4, 11527, Athens (Greece)
2. Departamento de Astronomia (IAGUSP), Universidade de Sao Paulo, Rua do Matao, 1226, 05508-900, Sao Paulo (Brazil)

We discuss the properties of homogeneous and isotropic flat cosmologies in which the present accelerating stage is powered only by the gravitationally induced creation of cold dark matter (CCDM) particles ({Omega}{sub m}=1). For some matter creation rates proposed in the literature, we show that the main cosmological functions such as the scale factor of the universe, the Hubble expansion rate, the growth factor, and the cluster formation rate are analytically defined. The best CCDM scenario has only one free parameter and our joint analysis involving baryonic acoustic oscillations + cosmic microwave background (CMB) + SNe Ia data yields {Omega}-tilde{sub m}=0.28{+-}0.01 (1{sigma}), where {Omega}-tilde{sub m} is the observed matter density parameter. In particular, this implies that the model has no dark energy but the part of the matter that is effectively clustering is in good agreement with the latest determinations from the large-scale structure. The growth of perturbation and the formation of galaxy clusters in such scenarios are also investigated. Despite the fact that both scenarios may share the same Hubble expansion, we find that matter creation cosmologies predict stronger small scale dynamics which implies a faster growth rate of perturbations with respect to the usual {Lambda}CDM cosmology. Such results point to the possibility of a crucial observational test confronting CCDM with {Lambda}CDM scenarios through a more detailed analysis involving CMB, weak lensing, as well as the large-scale structure.

• OSTI ID: 21410093
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 2 Vol. 82; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
79 ASTRONOMY AND ASTROPHYSICS
COSMOLOGY
DENSITY
DISTURBANCES
ELECTROMAGNETIC RADIATION
EXPANSION
GALAXY CLUSTERS
HUBBLE EFFECT
MATTER
MICROWAVE RADIATION
NONLUMINOUS MATTER
OSCILLATIONS
PARTICLES
PERTURBATION THEORY
PHYSICAL PROPERTIES
RADIATIONS
RELICT RADIATION
UNIVERSE