Cosmological equation of state and interacting energies

Abstract

In this paper the coupling between dark energy and the other components of the cosmological fluid has been studied. Firstly, it will be shown that the application of general cosmological equations, deduced by the authors in a previous work, to the known data of the Abell cluster A586 using the Layzer-Irvine theory gives similar results compared to the work of other authors. The aforesaid method present some problems: the application of an approximate theory (Layzer-Irvine theory), it has only one experimental datum and finally, it gives results that are a bit difficult to admit considering a physical reasoning. In order to avoid the abovementioned problems, a way to study the coupling of dark energy with other Universe components has been shown. The results obtained have a sensible physical behavior. They also fix the required functionality of the product wΛΩΛ in order to verify the main known properties of the Universe's behavior. Finally, these results permit to make predictions about a set of different cosmological properties.

Accelerated expansion of the universe based on particle creation–destruction processes and dark energy in FLRW universes

“…It seems well proven that the universe is experiencing an acceleration process [1][2][3]. Physicists have elaborated various answers [4] to explain this accelerated state, among them, the following may be mentioned: the existence of a new kind of energy (called 'dark energy' that we could consider to include Einstein's famous cosmological constant) [5], matter creation [6][7][8][9], and a whole set of theories that modify or go beyond the General Theory of Relativity, such as F(R) [10].…”

The Layzer-Irvine equation in theories with non-minimal coupling between matter and curvature

“…These relations have been used to study the interaction between the dark components of the Universe in galaxy clusters as Abell 586 and Abell 1689 [18][19][20][21], of dark energy components leading to structure formation [22,23], in the context of f (R) gravity [24] and scalar-tensor theories [25], and for modified gravitational potentials of the form ϕ (a, | − → r 1 − − → r 2 |), where the cosmological evolution appears in terms of the scale factor, a (t) [26].…”