Black Hole Encircled by a Thin Disk: Fully Relativistic Solution* * Dedicated to our teacher, colleague, and friend, Professor Oldřich Semerák, on the occasion of his 60th orbit around the Sun. Oldřich’s well-known lectures—famous not only among us (former) students of “math-phys” in Prague—were the first impulse that led us to devote our studies to general relativity.

Abstract

We give a full metric describing the gravitational field of a static and axisymmetric thin disk without radial pressure encircling a Schwarzschild black hole. The disk density profiles are astrophysically realistic, stretching from the horizon to radial infinity, yet falling off quickly at both these locations. The metric functions are expressed as finite series of Legendre polynomials. The main advantages of the solution are that (i) the disks have no edges, so their fields are regular everywhere (outside the horizon), and (ii) all nontrivial metric functions are provided analytically and in closed forms. We examine and illustrate basic properties of the black hole−disk spacetimes.