FieldStrength[mu, nu, a] is the field strength tensor
\partial _{\mu } A_{\nu }^a - \partial _{\nu }
A_{\mu }^a + g_s A_{\mu }^b A_{\nu }^c f^{abc}.
FieldStrength[mu, nu] is the field strength tensor (\partial _{\mu } A_{\nu}- \partial_{\nu }
A_{\mu}).
The name of the field (A) and the
coupling constant (g) can be set
through the options or by additional arguments. The first two indices
are interpreted as type LorentzIndex, except
OPEDelta, which is converted to
Momentum[OPEDelta].
FieldStrength[\[Mu], \[Nu]]F_{\mu \nu }^{}
FieldStrength[\[Mu], \[Nu], a]F_{\mu \nu }^a
FieldStrength[\[Mu], \[Nu], Explicit -> True]\left.(\partial _{\mu }A_{\nu }\right)-\left.(\partial _{\nu }A_{\mu }\right)
FieldStrength[\[Mu], \[Nu], a, Explicit -> True]g_s f^{a\text{b19}\;\text{c20}} A_{\mu }^{\text{b19}}.A_{\nu }^{\text{c20}}+\left.(\partial _{\mu }A_{\nu }^a\right)-\left.(\partial _{\nu }A_{\mu }^a\right)
FieldStrength[\[Mu], \[Nu], a, CouplingConstant -> -SMP["g_s"], Explicit -> True]-g_s f^{a\text{b21}\;\text{c22}} A_{\mu }^{\text{b21}}.A_{\nu }^{\text{c22}}+\left.(\partial _{\mu }A_{\nu }^a\right)-\left.(\partial _{\nu }A_{\mu }^a\right)