  Singular behavior of the Laplace operator in spherical coordinates is
investigated. It is shown that in course of transition to the reduced radial
wave function in the Schrodinger equation there appears additional term
consisting the Dirac delta function, which was unnoted during the full history
of physics and mathematics. The possibility of avoiding this contribution from
the reduced radial equation is discussed. It is demonstrated that for this aim
the necessary and sufficient condition is requirement the fast enough falling
of the wave function at the origin. The result does not depend on character of
potential:is it regular or singular. The various manifestations and
consequences of this observation are considered as well. The cornerstone in our
approach is the natural requirement that the solution of the radial equation at
the same time must obey to the full equation.
