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CovariantD

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Description

CovariantD[mu, a, b] is the covariant derivative for a bosonic field. CovariantD[mu] is the covariant derivative for a fermionic field. CovariantD[OPEDelta, a, b] is a short form for CovariantD[mu,a,b]*FourVector[OPEDelta, mu]. CovariantD[{OPEDelta, a, b}, {n}] yields the product of m operators., where n is an integer. CovariantD[OPEDelta, a, b, {m, n}] gives the expanded form of CovariantD[OPEDelta, a, b]^m up to order g^n for the gluon, where n is an integer and g the couplingconstant indicated by the setting of the option CouplingConstant. CovariantD[OPEDelta, {m, n}] gives the expanded form of CovariantD[OPEDelta]^m up to order g^n of the fermionic field.

Possible settings of PartialD are: LeftPartialD, LeftRigthPartialD, RightPartialD. The default setting of QuantumField is GaugeField.

See also: LeftPartialD, LeftRightPartialD, RightPartialD.

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Examples

The first argument of CovariantD is intepreted as type LorentzIndex, except for OPEDelta, which is type Momentum.

This givesthe partial derivative contracted with

The expansion up to first order in the coupling constant

The expansion up to second order in the

Converted from the *Mathematica* notebook CovariantD.nb