ABSTRACT
A free particle is shown to possess any non-negative energy value. Its position is described by a localized wave function called a wave packet. The solution to the particle in infinite potential well problem displays how the concept of energy quantization appears in quantum mechanics. Like the particle in an infinite well, the particle in a finite well shows discretization of energy. But unlike the particle in an infinite well, the particle in a finite well exhibits a non-zero probability of being found outside the well leading to the concept of quantum-mechanical tunneling.
