CCDM model with spatial curvature and the breaking of ''dark degeneracy''

Journal Article · Fri Jan 01 04:00:00 EST 2016 · Journal of Cosmology and Astroparticle Physics

DOI:https://doi.org/10.1088/1475-7516/2016/01/014· OSTI ID:22525080

Jesus, J. F. ^[1]

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1. Universidade Estadual Paulista ''Júlio de Mesquita Filho'', Campus Itapeva, Rua Geraldo Alckmin 519, 18409-010, Vila N. Sra. de Fátima, Itapeva, SP (Brazil)

Creation of Cold Dark Matter (CCDM), in the context of Einstein Field Equations, leads to a negative creation pressure, which can be used to explain the accelerated expansion of the Universe. Recently, it has been shown that the dynamics of expansion of such models can not be distinguished from the concordance ΛCDM model, even at higher orders in the evolution of density perturbations, leading at the so called ''dark degeneracy''. However, depending on the form of the CDM creation rate, the inclusion of spatial curvature leads to a different behavior of CCDM when compared to ΛCDM, even at background level. With a simple form for the creation rate, namely, Γ∝1/H , we show that this model can be distinguished from ΛCDM, provided the Universe has some amount of spatial curvature. Observationally, however, the current limits on spatial flatness from CMB indicate that neither of the models are significantly favored against the other by current data, at least in the background level.

• OSTI ID: 22525080
• Journal Information: Journal of Cosmology and Astroparticle Physics, Journal Name: Journal of Cosmology and Astroparticle Physics Journal Issue: 01 Vol. 2016; ISSN 1475-7516
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
COMPARATIVE EVALUATIONS
COSMOLOGICAL CONSTANT
COSMOLOGICAL MODELS
COSMOLOGY
DENSITY
DISTURBANCES
EINSTEIN FIELD EQUATIONS
EXPANSION
NONLUMINOUS MATTER
PERTURBATION THEORY
UNIVERSE