Circular motion around a rotating black hole in quintessential dark energy

Abstract

This paper investigates the circular motion of neutral test particles orbiting near Kerr–Newman black hole in the presence of quintessential dark energy and cosmological constant. We limit our analysis to the equatorial plane and explore the properties of both time-like and null geodesics. The behavior of the specific energy and the angular momentum of the co-rotating as well as the counter rotating particles is analyzed. We also discuss the stable regions with respect to the horizons, radius of photon sphere and the so called static radius. We have shown that the stable points are always less than the static radius while they exceed the radius of photon orbit. The energy extraction, negative energy state and energy gain during the Penrose process is also discussed. It is found that more energy can be gained during the Penrose process in the presence of dark energy as compared to the charge and spin of the said black hole.