Effect of Accretion on the evolution of Primordial Black Holes in the context of Modified Gravity Theories

Abstract

We investigates the effect of accretion of cosmic fluid on the evolution of Primordial Black Holes (PBHs) within the framework of Modified gravity theories. We consider a general form of the Hubble parameter, reflecting a general class of modified gravity theories and bouncing models. We then study the effect of such modified dynamics on PBH in the presence of Hawking radiation and accretion of surrounding materials. We investigate how the evolution of PBHs is influenced by accretion across different cosmological eras, considering the radiation, matter, and dark energy-dominated phases like phantom and quintessence for linear equation of state. We further incorporated Non-linear Equations of State such as Chaplygin Gas, Modified Chaplygin gas, Van der Waals model, Polytropic Fluid model. The study systematically analyzes the mass variation of PBHs in the presence of such different cosmological environments. The results will contribute to the understanding of PBH formation and evolution in modified theory of gravity, and their possibility of being detected with future experiments.