Relativistic hydrogen atom revisited

The hydrogen atom is solved using a simple method. We show that this system has an exact solution that can be written in terms of Laguerre polynomials of noninteger index, instead of the hypergeometric series. This point is i mportant because Laguerre polynomials of integer index appear in the soluti on of the nonrelativistic hydrogen atom, giving students a more unified poi nt of view for this system. (C) 2000 American Association of Physics Teache rs.