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
Kavli Institute for the Physics and Mathematics of the Universe Kavli Institute for the Physics and Mathematics of the Universe The Kavli Institute for the Physics and Mathematics of the Universe (IPMU) is an international research institute for physics and mathematics situated in Kashiwa, Japan, near Tokyo. Its full name is ""Kavli Institute for the Physics and Mathematics of the Universe, The University of Tokyo Institutes for Advanced Study, the University of Tokyo, Kashiwa, Japan"". The main subjects of study at IPMU are particle physics, high energy physics, astrophysics, astronomy and mathematics. The institute addresses five key questions: "How did the universe begin? What is its fate? What is it