Kramers–Heisenberg formula Kramers–Heisenberg formula The Kramers–Heisenberg dispersion formula is an expression for the cross section for scattering of a photon by an atomic electron. It was derived before the advent of quantum mechanics by Hendrik Kramers and Werner Heisenberg in 1925, based on the correspondence principle applied to the classical dispersion formula for light. The quantum mechanical derivation was given by Paul Dirac in 1927. The Kramers–Heisenberg formula was an important achievement when it was published, explaining the notion of "negative absorption" (stimulated emission), the Thomas–Reiche–Kuhn sum rule, and inelastic scattering — where the energy of the scattered photon may be larger
The Tao of Physics theoretical physics and Eastern mysticism and was at first "helped on my way by 'power plants'" or psychedelics, with the first experience "so overwhelming that I burst into tears, at the same time, not unlike Castaneda, pouring out my impressions to a piece of paper". (p. 12, 4th ed.) Capra later discussed his ideas with Werner Heisenberg in 1972, as he mentioned in the following interview excerpt: I had several discussions with Heisenberg. I lived in England then [circa 1972], and I visited him several times in Munich and showed him the whole manuscript chapter by chapter. He was very