FeynCalc manual (development version)

SUNTF

SUNTF[{a}, i, j] is the SU(N) T^a generator in the fundamental representation. The fundamental indices are explicit.

See also

Overview, SUNFindex, SUNT, SUNSimplify.

Examples

SUNTF[a, i, j]

T_{ij}^a

SUNTF[{a, b}, i, j]

\left(T^aT^b\right){}_{ij}

SUNTF are c-numbers, hence they are commutative objects and do not require a dot

SUNTF[{a, b}, i, j] SUNTF[{c, d}, j, k]

\left(T^aT^b\right){}_{ij} \left(T^cT^d\right){}_{jk}

SUNTF[{a, b}, i, j] SUNTF[{c, d}, j, k] // SUNSimplify

\left(T^aT^bT^cT^d\right){}_{ik}

A chain with closed indices is automatically converted into a trace

SUNTF[{a, b}, i, j] SUNTF[{c, d}, j, i] // SUNSimplify

\text{tr}\left(T^a.T^b.T^c.T^d\right)

SUNDelta[a, b] SUNTF[{a, b}, i, j] SUNTF[{c, d}, j, i] // SUNSimplify

\frac{1}{2} C_F \delta ^{cd}

SUNTF[{a, b}, i, j] // FCI // StandardForm

(*SUNTF[{SUNIndex[a], SUNIndex[b]}, SUNFIndex[i], SUNFIndex[j]]*)