Some remarks on the hydrogen atom

The path integral for the Green's function involving the Coulomb potential in combination with the Kustaanheimo-Stiefel transformation is used to generate the atomic orbitals of the nonrelativistic hydrogen atom as various combinations of the product of one-dimensional isotropic harmonic oscillator wave functions. The use of the transformation is justified, by connecting the homogeneous space with the quotient space in the Feynman quantization formalism.