Two answers required. Assuming that the number of particles is a continuous quantity yields these two scientists’ approximation for the degeneracy of energy states in a gas in a box. An ODE named for these scientists models charge density of positive ions when charge vanishes at finite radius and neutral atoms when charge vanishes only asymptotically. When the ratio of the wave vector to a quantity named for one of these scientists vanishes, the long-distance limit of Lindhard theory named for these scientists applies. A model named after these scientists predicts that kinetic energy is proportional to the integral of electron density to the five-thirds power. A predecessor to (*) DFT is a semiclassical model of electronic structure of many-body systems named for these scientists. For 10 points, name these two physicists, one of whom names a type of special relativistic precession, and the other of whom names a national lab in Batavia, Illinois. ■END■
ANSWER: Llewellyn Thomas AND Enrico Fermi [accept Llewellyn Hilleth Thomas in place of “Llewellyn Thomas”; accept Thomas–Fermi model, Thomas–Fermi screening length, Thomas–Fermi approximation, Thomas–Fermi equation, or Thomas–Fermi screening; prompt on TF model]
<Geoffrey Wu, Physics>
= Average correct buzz position