2013/05/31 by Ozgur Akarsu, Tekin Dereli, Suresh Kumar +1 · 1 citation
Physics and Astronomy · #gr-qc #astro-ph.CO
paper · pdf · doi:10.1140/epjp/i2014-14022-6
published as The European Physical Journal Plus 129 (2014) 22 · 15 pages, 3 figures, 9 tables; matches the version published in The European Physical Journal Plus
arxiv created 2014/02/04 · arxiv updated 2014/02/05
The parametrizations q=q0+q1 z and q=q0+q1 (1-a/a0) (Chevallier-Polarski-Linder parametrization) of deceleration parameter, which are linear in cosmic redshift z and scale factor a, have been frequently utilized in the literature to study kinematics of Universe. In this paper, we follow a strategy that leads to these two well known parametrizations of deceleration parameter as well as an additional new parametrization q=q0+q1(1-t/t0), which is linear in cosmic time t. We study the features of this linearly time-varying deceleration parameter in contrast with the other two linear parametrizations. We investigate in detail the kinematics of the Universe by confronting the three models with the latest observational data. We further study the dynamics of the Universe by considering the linearly time-varying deceleration parameter model in comparison with the standard ΛCDM model. We also discuss future of the Universe in the context of the models under consideration.