2018/07/31 by Paxy George, Titus K Mathew, V. Mohammed Shareef +1
Physics and Astronomy · #Acceleration #Black Holes and Theoretical Physics #Cold dark matter #Cosmological constant #Cosmology and Gravitation Theories #Coupling (piping) #Dark Matter and Cosmic Phenomena #Dark energy #De Sitter universe #Deceleration parameter #Quintessence #Vacuum energy #Vacuum state #gr-qc
paper · pdf · doi:10.1142/s0218271819500603
17 pages, 12 figures
openalex created_date 2018/07/10 · arxiv created 2018/08/29 · openalex publication_date 2018/11/13 · arxiv updated 2019/03/27 · openalex updated_date 2026/08/05
Earlier studies have shown that in a two component model of the universe with dark matter and the running vacuum energy, which is phenomenologically a combination of [Formula: see text] and [Formula: see text] either eternal deceleration or acceleration is produced in the absence of a bare constant in the density of the running vacuum. In this paper, we have shown that in the interaction scenario, where the interaction between matter and vacuum is introduced through a phenomenological term, the two component model is capable of causing a transition from a prior decelerated to a later accelerated epoch without a bare constant in the running vacuum density. On contrasting the model with the cosmological data, we have found that the interaction coupling constant is small enough for a slow decay of the running vacuum. The model is subjected to dynamical system analysis, which revealed that the end de Sitter phase of the model is a stable one. We did an analysis on the thermal behavior of the system, which shows that the entropy is bounded at the end stage so that the system behaves like an ordinary macroscopic system. Apart from these, we have also performed the state finder diagnostic analysis which implies the quintessence nature of running vacuum and confirms that the model will approach the standard [Formula: see text]CDM in the future.