Is it possible to easily simplify the difference of conjugate pairs?
In particular, if there’s just a single variable, then
FullSimplify[a - Conjugate[a]]
2 I Im[a]
But trying to do the same thing with a slightly more complex expression fails:
FullSimplify[a Conjugate[b] - Conjugate[a] b]
a Conjugate[b] - Conjugate[a] b
I have found one solution (answered below) but it relies on a
FullSimplify which doesn’t seem very optimal.