An Etymological Dictionary of Astronomy and Astrophysics

A system of ten non-linear → partial differential equations in the theory of → general relativity which relate the curvature of → space-time with the distribution of matter-energy. They have the form: G_μν = -κ T_μν, where G_μν is the → Einstein tensor (a function of the → metric tensor),
κ is a coupling constant called the → Einstein gravitational constant, and T_μν is the → energy-momentum tensor. The field equations mean that the curvature of space-time is due to the distribution of mass-energy in space. A more general form of the field equations proposed by Einstein is:

G_μν + Λg_μν = - κT_μν, where Λ is the → cosmological constant.

See also: Named after Albert Einstein (1879-1955); → field; → equation.