FEYN CALC SYMBOL

ChangeDimension


changes all LorentzIndex and Momenta in exp to dimension dim (and also Levi-Civita-tensors, Dirac slashes and Dirac matrices).

ExamplesExamplesopen allclose all

Basic Examples  (1)Basic Examples  (1)

Remember that LorentzIndex[mu, 4] is simplified to LorentzIndex[mu] and Momentum[p, 4] to Momentum[p]. Thus the fullowing objects are defined in four dimensions.
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This changes all non-4-dimensional objects to 4-dimensional ones.
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Consider the following list of 4- and D-dimensional object.
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Any explicit occurence of D (like in f(D)) is not replaced by ChangeDimension.
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The option Dimension of Eps must be changed too, since with the default setting Dimension4 the arguments of Eps are automatically changed to 4 dimensions.
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