An Etymological Dictionary of Astronomy and Astrophysics

The mathematical description of the interval (→ space-time separation) between → events (“points” in space-time) in a → homogeneous and → isotropic → Universe. It results from an exact solution of → Einstein’s field equations of → general relativity.
Under the assumptions, the Robertson-Walker interval is expressed by:

ds² = c²dt² - R²(t) [dr²/(1 - kr²) + r²dθ² +
r²sin²θ dθ²)].

Same as Friedmann-Lemaître-Robertson-Walker metric. Compare → Minkowski metric.

See also: Named after Howard Percy Robertson (1903-1961), American mathematician and physicist, and Arthur Geoffrey Walker (1909-2001), British mathematician and physicist, for their contributions to physics and physical cosmology; → metric.