Equation Icon  ( ) ¯δ ¯ε tail ⟨γ¯α¯β;¯γ⟩ = − 4m u(α¯R β¯)¯δ¯γ¯ε + R ¯α¯δ¯β¯εu ¯γ u u + γ¯α¯β¯γ, (523 )