Various quantum states are described as existing in one state or another, but nothing in between. A simplified example is an electron moving from one shell to another. When that electron transfers from one orbit to another does the electron not exist for a period of time or is the transfer instantaneous so the electron effectively changes location faster the speed of light? I understand this question is complicated by the uncertainty principle and it impossible to assign a precise location and momentum to the electron at any given moment. However, I hope you understand the essence of the question, which is do quantum leaps happen at a mundane speed of light pace (where the electron is not in a quantum state for a brief but finite period) or literally instantaneously?