Impact of dynamical dark energy on black hole dynamics in an accelerated expanding universe

Abstract

In this work, an interacting dark energy model is introduced for explaining the dynamical behaviour of our universe, where dark energy is evolved through continuous interaction with matter. Basing on this model, we have first computed the basic parameters like the density of dark energy, which is further utilized to illustrate the universe’s expansion dynamics. Our study suggests that the interacting nature of dark energy is sufficient to explain the observed accelerated expansion of present universe, if it is quintessence type. While the equation of state parameter (${\gamma }_{\varphi }$) for quintessence ranges between 0 and $-1$, our analysis predicts that accelerating nature of universe’s expansion can only occur, if the present value of ${\gamma }_{\varphi }$ is less (more negative) than $-0.7866$. It is also concluded that the universe’s expansion would undergo a decelerating phase in the early epoch and would shift to accelerated expansion, around $0.655t_0$, with $t_0$ representing the current age of our universe. Further, our model indicates that the accelerated expanding phase will continue for ever. Our focus also attributes to the mass evolution of Schwarzschild type black hole. In this context we consider the accumulation of energy-matter and the quantum mechanical Hawking evaporation as the active ingredients for evolution of black holes’ mass and found that accretion efficiency ($f$) creates different patterns of mass variations. Again, we have taken a look on the astrophysical constraints that affected the abundance of black holes and found that with increasing accretion efficiency, limits imposed on the black holes’ initial mass fraction would become more tightened.