Chern-Simons 3-form (source code)

= Chern-Simons 3-form
{c}
{wiki=Chern–Simons_form}

The Chern-Simons 3-form
$$
Y=\frac1{8\pi^2}\operatorname{Tr}\left(A\wedge dA+\frac23A\wedge A\wedge A\right)
$$
satisfies $dY=C_2$.