Equation Icon  ( ) 2( ) Firecoil = -2G-- Qjl′′′Qkj ′′′− Qjl′′′ Qkj′′′ 𝜖kli + 2q--ηj′′ηkI′′− ηj′′ηkR′′𝜖kji 15c6√ -- Spin Mass Mass Spin 3c4 R I 4 2q ( j′′ ji′′′ j′′ ji′′′) 4 ( jl′′′ kj′′′ jl′′′ kj′′′) − ----5- ηR Q E + ηI Q M − -----6 QM Q E − QE Q M . (6.53 ) 15c 135c