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Pair

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Description

Pair[x, y] is the head of a special pairing used in the internal representation: x and y may have heads LorentzIndex or Momentum. If both x and y have head LorentzIndex, the metric tensor is understood. If x and y have head Momentum, a scalar product is meant. If one of x and y has head LorentzIndex and the other Momentum, a Lorentz vector is understood.

See also: FourVector, FV, FVD, MetricTensor, MT, MTD, ScalarProduct, SP, SPD.

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Examples

This represents a four-dimensional metric tensor.

This is a D-dimensional metric tensor.

Converted from the *Mathematica* notebook Pair.nb