SUNIndex[a]
is an SU(N)
index in the adjoint representation. If the argument is an integer,
SUNIndex[a]
turns into
ExplicitSUNIndex[a]
.
Overview, ExplicitSUNIndex, SUNDelta, SUNF.
[i] SUNIndex
i
[i] // StandardForm
SUNIndex
(*SUNIndex[i]*)
[2] SUNIndex
2
[2] // StandardForm
SUNIndex
(*ExplicitSUNIndex[2]*)
[i, j] // FCI // StandardForm
SUNDelta
(*SUNDelta[SUNIndex[i], SUNIndex[j]]*)