An Etymological Dictionary of Astronomy and Astrophysics

A quantity, denoted L_d, describing a continuous system in the → Lagrangian formalism, and defined as the → Lagrangian per unit volume. It is related to the Lagrangian L by:
L = ∫∫∫L_d d³V.

Lagrangian density is often called Lagrangian when there is no ambiguity.

See also: → Lagrangian; → density.