Equation Icon  | μν ∮ d Ωy [ ∂ ∂ ] | h H (τ,xi) = ---- ---(ρhμν(τ ′,yi)) + --′(ρhμν(τ′,yi)) || . (73 ) ∂C (τ,xi) 4π ∂ ρ ∂τ τ′=0,ρ= |⃗x−⃗y|=τ