Explicit Analytical Representations for the Schwarzschild Radial Equation via Hypergeometric and Frobenius Expansions

J. G. R. Valangelis, Ailton C. Nascimento, Helder A. S. Costa

The massive Klein-Gordon equation on the Schwarzschild exterior reduces to a radial differential equation of confluent-Heun type. We present its exact reduction by rigorously retai…