Speaker
Description
Recent cosmological observations confirm that the universe is undergoing a late-time accelerated expansion. To account for this phenomenon, an exotic component with negative pressure, known as dark energy, has been proposed. Among various dark energy models, the Holographic Dark Energy (HDE) model, motivated by the holographic principle of quantum gravity, has gained significant attention.
In this work, we investigate a generalized version of HDE based on Rényi entropy, namely the Rényi Holographic Dark Energy (RHDE) model, which arises from modifications of the Bekenstein–Hawking entropy relation. Considering the Hubble horizon as the infrared (IR) cutoff, we analyze the cosmological dynamics of the RHDE model within the framework of dynamical systems theory.
The study is carried out for three distinct scenarios: non-interacting, linearly interacting cases between dark energy and dark matter. The qualitative behavior of the cosmological evolution is examined through phase space analysis, and the stability of the system is investigated around hyperbolic critical points. Furthermore, we explore the effective fluid description of the model and analyze the evolution of the equation of state parameter, along with the matter and dark energy density parameters.
The results provide insights into the viability of the RHDE model in explaining the late-time acceleration of the universe and its dynamical stability under different interaction scenarios.