Explore: Einstein Equations

In the general theory of relativity, the Einstein field equations (EFE; also known as Einstein's equations) relate the geometry of spacetime to the distribution

frequently used important special forms of the relation are: Einstein–Smoluchowski equation, for diffusion of charged particles: D = μ q k B T q {\displaystyle

closed form) solution of the Einstein field equations whose derivation does not invoke simplifying approximations of the equations, though the starting point

units of measurement. The principle is described by the physicist Albert Einstein's formula:  E = m c 2 {\displaystyle E=mc^{2}} . In a reference frame where

Hamiltonian, and thereby write the equations of motion for general relativity in the form of Hamilton's equations. In addition to the twelve variables

pseudo-Riemannian manifold. In general relativity, it occurs in the Einstein field equations for gravitation that describe spacetime curvature in a manner that

Solutions of the Einstein field equations are metrics of spacetimes that result from solving the Einstein field equations (EFE) of general relativity.

1930s. The Friedmann equations build on three assumptions: the Friedmann–Lemaître–Robertson–Walker metric, Einstein's equations for general relativity

is determined by the Einstein field equations themselves, not by a new law. Accordingly, Einstein proposed that the field equations would determine the

Correspondingly, the 5D Einstein equations yield the 4D Einstein field equations, the Maxwell equations for the electromagnetic field, and an equation for the scalar