SYMMETRY OPERATORS AND SEPARATION OF VARIABLES FOR SPIN-WAVE EQUATIONS IN OBLATE SPHEROIDAL COORDINATES

A family of second-order differential operators that characterize the solution of the massless spin s field equations, obtained via separation of variables in oblate spheroidal coordinates and using a null tetrad is found. The first two members of the family also characterize the separable solutions in the Kerr space-time. It is also shown that these operators are symmetry operators of the field equations in empty space-times whenever the space-time admits a second-order Killing-Yano tensor. © 1990 American Institute of Physics.