Traditionally, a quantum harmonic oscillator model is used to describe the tiny vibrations in a diatomic molecule, but the description is also universal in the sense that it can be extended to a variety of other situations in physics and beyond. One example of this is illustrated in a new study, in which researchers show that the restoring force in a vibrating quantum harmonic oscillator provides a good approximation of the market force that restores a fluctuating stock return to equilibrium.