Charged dust in higher curvature geometry

Abstract

We analyze the configuration of charged dust in the context of the higher dimensional and higher curvature Einstein–Gauss–Bonnet–Maxwell theory. With the prescription of dust, there remains one more prescription to be made in order to close the system of equations of motion. The choice of one of the metric potentials appears to be the only viable way to proceed. Before establishing exact solutions, we examine conditions for the existence of physically reasonable charged dust fluids. It turns out that the branches of the Boulware–Deser metric representing the exterior gravitational field of a neutral spherically symmetric Einstein–Gauss–Bonnet distribution, serve as upper and lower bounds for the spatial potentials of physically reasonable charged dust in Einstein–Gauss–Bonnet–Maxwell gravity. Some exact solutions for 5 and 6 dimensional charged dust hyperspheres are exhibited in closed form. In particular the Einstein ansatz of a constant temporal potential while defective in 5 dimensions actually generates a model of a closed compact astrophysical object in 6 dimensions. A physically viable 5 dimensional charged dust model is also contrasted with its general relativity counterpart graphically.