Luttinger

Luttinger is a surname of German origin. In physics, the name is associated with key ideas about interacting electrons, especially in one dimension. Luttinger’s theorem asserts that the Fermi surface volume in a system of interacting fermions is determined by particle density and remains unchanged by interactions under broad conditions. The result provides a constraint on how charges fill momentum space in both lattice and continuum models.

Another major concept is the Luttinger liquid, a theoretical description of interacting fermions in one dimension in which low-energy excitations are collective bosonic modes rather than individual quasiparticles; correlation functions exhibit power-law decays with exponents controlled by interaction strength. The Tomonaga–Luttinger model is an exactly solvable framework that embodies these features and serves as a standard reference for one-dimensional quantum many-body physics.

The Luttinger parameter, commonly denoted K, characterizes interaction strength in these theories and governs scaling of correlation functions and transport properties.

The terms Luttinger’s theorem, Luttinger liquid, and Tomonaga–Luttinger model reflect the influence of the physicist’s work on condensed matter theory and related fields.