Atomic, molecular, and optical physics the origin of the index of refraction treated an electron in an atomic system classically according to the model of Paul Drude and Hendrik Lorentz. The theory was developed to attempt to provide an origin for the wavelength-dependent refractive index "n" of a material. In this model, incident electromagnetic waves forced an electron bound to an atom to oscillate. The amplitude of the oscillation would then have a relationship to the frequency of the incident electromagnetic wave and the resonant frequencies of the oscillator. The superposition of these emitted waves from many oscillators would then lead to a wave which
Interface metaphor to making it resemble something the users understand. Experts, on the other hand, understand what is going on with the technical aspects of an interface metaphor. They know what they want to do and they know how to do it—and so they design shortcuts to facilitate achieving their goals. While the concept behind interface metaphors appears simple (to promote more efficient facilitation of a computer), a lack of empirical evidence exists to support these claims. Little research has actually been completed that demonstrates the benefits of implementing metaphors in computer systems as well as what makes a metaphor most effective.