Contrary to the previous belief, it is found that the time dependent Schrödinger equation is not always reduced to the Hamilton–Jacobi equation in the ℏ→0 limit. An explicit example is given.
In this article, we will answer a question posed in the book Classical Mechanics by H. Goldstein: ``"Is the Hamilton-Jacobi equation the short wavelength limit of the Schrödinger equation?" But, before that, we will identify an essential element that will take us from the Hamilton-Jacobi equation to the dynamic equation of non-relativistic quantum mechanics for a function ψ through an exact procedure. This element is the linear independence of the functions ψ and ψ* (their complex conjugate). Their independence is demonstrated for physical systems where the acting physical potential does not explicitly depend on time. Proceeding in reverse, from the Schrödinger equation, we obtain the Hamilton-Jacobi equation, exactly, without additional terms.
We find the form of the potential depending on the coordinates and the time such that a solution, S, of the Hamilton--Jacobi equation yields an exact solution, exp(iS/ℏ), of the corresponding Schrödinger equation.