On the equivalence of Lambda(t) and gravitationally induced particle production cosmologies

Author(s)

Graef, L. L. ^[1] ; Costa, F. E. M. ^{[2, 3]} ; Lima, J. A. S. ^[2]

Affiliation

^[1] Univ Sao Paulo, Inst Fis, BR-05508900 Sao Paulo - Brazil

^[2] Univ Sao Paulo, Dept Astron, BR-05508900 Sao Paulo - Brazil

^[3] Univ Fed Rural Semi Arido, BR-59900000 Pau Dos Ferros, RN - Brazil

• Document type: Journal article
• Source: Physics Letters B; v. 728, p. 400-406, JAN 20 2014.
• Web of Science Citations: 20

Abstract

The correspondence between cosmological models powered by a decaying vacuum energy density and gravitationally induced particle production is investigated. Although being physically different in the physics behind them we show that both classes of cosmologies under certain conditions can exhibit the same dynamic and thermodynamic behavior. Our method is applied to obtain three specific models that may be described either as A(t)CDM or gravitationally induced particle creation. In the point of view of particle production models, such cosmologies can be interpreted as a kind of one-component unification of the dark sector. By using current type la supernovae data, recent estimates of the cosmic microwave background shift parameter and baryon acoustic oscillations measurements we also perform a statistical analysis to test the observational viability within the two equivalent classes of models and we obtain the best-fit of the free parameters. By adopting the Akaike information criterion we also determine the rank of the models considered here. Finally, the particle production cosmologies (and the associated decaying A(t)-models) are modeled in the framework of field theory by a phenomenological scalar field model. (C) 2013 The Authors. Published by Elsevier B.V. All rights reserved. (AU)

• FAPESP's process: 11/13018-0 - Dark energy and F(R) theories: theoretical and observacional aspects
• Grantee: Francisco Ernandes Matos Costa
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 04/13668-0 - Cosmology in the era of precision: dark energy, dark matter and background cosmic radiation
• Grantee: Jose Ademir Sales de Lima
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 12/09380-8 - Vacuum decay, warm inflation and its connections with the current accelerated stage of the universe: conceptual aspects and observational tests
• Grantee: Leila Lobato Graef
• Support Opportunities: Scholarships in Brazil - Doctorate