The key element in the Padua Algorithm the
transformation t=tan
-1
(x). Since tan(
π
/2)= ∞.
This transforms r =
∞ to t=
π
/2
i.e.,
0<x<∞ is transformed to
0<t<
π
/2
[see Minelli et al. Nuovo Cimento,v.101 ,p. 1630 (1991)]
the Rarita-Schwinger Equation becomes: