Equation Icon  β [ ± ] [ + ] [ − ] S eff hμν = Sg hμν − Sg h μν i [ (1) β (1) β (2) β (2) β ] + -tr V+ G ++ − V− G− − + V+ G ++ − V− G− − 2 [ ] − itr V(+1)G β++ V+(1)G β++ + V (−1)Gβ− − V (−1)G β−− − 2V+(1)G β+− V−(1)G β− + . (195 ) 4