Volume 71, Number 2, July 2005
|Page(s)||179 - 185|
|Published online||10 June 2005|
Non-linear terms in 2D cosmology
Departamento de Física, Universidade Federal do Paraná Caixa Postal 19044, 81531-990, Curitiba, Brazil
Corresponding author: firstname.lastname@example.org
Accepted: 11 May 2005
In this work we investigate the behavior of two-dimensional (2D) cosmological models, starting with the Jackiw-Teitelboim (JT) theory of gravitation. A geometrical term, non-linear in the scalar curvature R, is added to the JT dynamics to test if it could play the role of dark energy in a 2D expanding universe. This formulation makes possible, first, the description of an early (inflationary) 2D universe, when the van der Waals (vdW) equation of state is used to construct the energy-momentum tensor of the gravitational sources. Second, it is found that for later times the non-linear term in R can generate an old 2D universe in accelerated expansion, where an ordinary matter-dominated era evolves into a decelerated/accelerated transition, giving to the dark energy effects a geometrical origin. The results emerge through numerical analysis, following the evolution in time of the scale factor, its acceleration, and the energy densities of constituents.
PACS: 04.50.+h – Gravity in more than four dimensions, Kaluza-Klein theory, unified field theories; alternative theories of gravity / 98.80.-k – Cosmology
© EDP Sciences, 2005
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.