Equation Icon  a α- β a b β a 1- b c a T = − iE ∧ E--Γαβ + E ∧ E - Tbβ + 2 E ∧ E T bc, (552 ) 1 1 R4 = -Eb-∧ Ea- ∧ Eα-∧ E β(Γ ab)αβ +--Ea-∧ Eb-∧ Ec-∧ EdRdcba, (553 ) 2 4! R = 1-Ea1-∧ ...∧ Ea5-∧ E α-∧ E β(Γ ) + 1-Ea1 ...Ea7R . (554 ) 7 5! a1...a5 αβ 7! a7...a1