An Etymological Dictionary of Astronomy and Astrophysics

A mapping of an infinite → space-time onto a finite one that may make the far away parts of the former accessible to study. The technique invented by Penrose defines an equivalence class of → metrics, g_ab being equivalent to ĝ_ab = Ω²g_ab,
where Ω
is a positive scalar function of the space-time that modifies the distance scale making the asymptotics of the physical metric accessible to study.

See also: → conformal; → compactification.