Equation Icon  g = − [1 + 2a ˆya + (a yˆa )2 + R ˆycˆyd + 𝒪 (s3)] , (129 ) tt a a 0c0d g = − 2-R ˆycˆyd + 𝒪 (s3), (130 ) ta 3 0cad g = δ (1 − R ˆycˆyd) + 𝒪 (s3). (131 ) ab ab 0c0d