I like to digest better:

We already knew that in Maxwell differential form equation we have:
$$
* d * F=0
$$
knew that in Yang-Mills differential form equation we have:
$$
* D * F=0
$$
here $D .=d .+ [A,.]$

But how we do understand $* d * $ operator and $* D * $ operator? Their the (differential/geometry) meaning? How do we make ourselves comfortable , even though we also knew the equation boils down to:

$$
\partial_\mu F^{\mu \nu}=0
$$
$$
D_\mu F^{\mu \nu}=0
$$
respectively. But how to think $* d * $ operator and $* D * $ operator differential/geometry-ly?

This post imported from StackExchange Physics at 2020-11-09 19:28 (UTC), posted by SE-user annie marie heart