I don't know if I'm understanding your question right, but I think you are trying to pose a deeper question than it might seem at first sight... In ordinary quantum mechanics, when you study the hydrogen atom, you derive a set of solutions for the electron wavefunction using the Schrödinger equation (with different values of the energy). These are the different orbitals in which the electron can live.
Now, in principle, these states are stationary, i.e., once you place an electron in an orbital, say the one defined by the quantum numbers $n=2$, $l=1$, $m=0$; the wavefunction does not change with time (technically, only its modulus squared is constant, but that's only a small detail since the energy remains the same), so basically the electron never returns to the ground state according to this theory. Obviously this must be wrong since we know that the electron does return to the ground state (or at least to a state with lower energy), and quite fast. The key point here is that the hydrogen atom is not an isolated system: even in vacuum, when you consider the electromagnetic field from a quantum field theory point of view you get that this vacuum field in some sense interacts with the hydrogen atom, causing the electron to decay to a lower energy state. I'm not an expert in these matters, so I won't try to explain in detail what this means basically because I have never worked out exactly how the process goes (maybe somebody else could develop this point?), but you can read something more here: