This method allows for the calculation of the small term's effects by an infinite series, and each term is a correction term to the solutions of the exactly calculable system.
An application of this method is the assumption that the motion of atomic nuclei are taken to be so much slower than the motion of electrons that, when calculating the motion of electrons, the nuclei can be taken to be in fixed positions, an example known as the Born-Oppenheimer approximation. This method allows for the calculation of the small term's effects by an infinite series, and each term is a correction term to the solutions of the exactly calculable system. FTP, identify this method of calculating in physics that divides a system into an exactly calculable part and a small term.
An application of this method is the assumption that the motion of atomic nuclei are taken to be so much slower than the motion of electrons that, when calculating the motion of electrons, the nuclei can be taken to be in fixed positions, an example known as the Born-Oppenheimer approximation.
{perturbation} theory