Taub–NUT space

The Taub–NUT metric (/tɔːb nʌt/ or /tɔːb ɛnjuːˈtiː/) is an exact solution to Einstein's equations, a cosmological model formulated in the framework of general relativity.

The Taub–NUT space was found by Abraham Haskel Taub (1951), and extended to a larger manifold by Ezra T. Newman, Louis A. Tamburino, and Theodore W. J. Unti (1963), whose initials form the "NUT" of "Taub–NUT".

Taub's solution is an empty space solution of Einstein's equations with topology R×S³ and metric

where

and m and l are positive constants.

Taub's metric has coordinate singularities at ${\displaystyle U=0,t=m+(m^{2}+l^{2})^{1/2}}$, and Newman, Tamburino and Unti showed how to extend the metric across these surfaces.

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