Quantum Tunneling
One of the rules of Quantum Physics is that because particles also exhibit wave-like behavior
(Wave-particle duality), if there's a particle on one side of a barrier and it can't cross to the
other side, the wave function still exists and actually extends a little bit to the other side of
the barrier as well. Therefore, the electron can disappear from one side and reappear on the other side,
collapsing the wave-function and seemingly moving instantaneously.
A phenomena known as "Quantum Mechanical Tunneling", This occurs frequently in our surroundings as well as
in the cosmos. It's mysterious and amazing!