Regular Article - Theoretical Physics
More on the holographic Ricci dark energy model: smoothing Rips through interaction effects?
Department of Theoretical Physics University of the Basque Country UPV/EHU, P.O. Box 644, 48080, Bilbao, Spain
2 IKERBASQUE, Basque Foundation for Science, 48011, Bilbao, Spain
3 Laboratory of Physics of Matter and Radiation, Mohammed First University, BP 717, Oujda, Morocco
4 Faculty of Physics, University of Warsaw, Pasteura 5, 02-093, Warsaw, Poland
5 School of Engineering Science, College of Engineering, University of Tehran, 11155-4563, Tehran, Iran
6 School of Astronomy, Institute for Research in Fundamental Sciences (IPM), 19395-5531, Tehran, Iran
* e-mail: email@example.com
Accepted: 29 March 2018
Published online: 23 April 2018
The background cosmological dynamics of the late Universe is analysed on the framework of a dark energy model described by an holographic Ricci dark energy component. Several kind of interactions between the dark energy and the dark matter components are considered herein. We solve the background cosmological dynamics for the different choices of interactions with the aim to analyse not only the current evolution of the universe but also its asymptotic behaviour and, in particular, possible future singularities removal. We show that in most of the cases, the Big Rip singularity, a finger print of this model in absence of an interaction between the dark sectors, is substituted by a de Sitter or a Minkowski state. Most importantly, we found two new future bouncing solutions leading to two possible asymptotic behaviours, we named Little Bang and Little Sibling of the Big Bang. At a Little Bang, as the size of the universe shrinks to zero in an infinite cosmic time, the Hubble rate and its cosmic time derivative blow up. In addition, at a Little sibling of the Big Bang, as the size of the universe shrinks to zero in an infinite cosmic time, the Hubble rate blows up but its cosmic time derivative is finite. These two abrupt events can happen as well in the past.
© The Author(s), 2018