Equation Icon  [ ] U ′ uβ′ = − 1-rgα′gβ′ R ′ ′ + R ′ ′Ωc − 1(R ′ + R ′Ωc )u ′ + O (r) (18.16 ) αβ ;β 2 α β α0β0 α0β c 3 β 0 βc α