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LDot

LDot[a,b] or a.b
represents the Lorentz 4-vector dot product .

Details and OptionsDetails and Options

  • Generic object that represents a Lorentz 4-vector dot product.
  • Built-in Mathematica function Dot must be called by its full name while Package-X is active.
  • LDot has attribute Orderless.
  • LDot[a,b] automatically expands if either a or b has head Plus.
  • Clear[LDot] clears all user defined values for LDot.

ExamplesExamplesopen allclose all

Basic Examples  (5)Basic Examples  (5)

A dot product of two 4-vectors:

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Enter directly using the infix operator ".":

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(Mathematica's built-in Dot must be spelled out in full while Package-X is active):

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Automatic expansion of dot products of linear combinations of four-vectors:

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Use Hold to keep linear combinations from expanding:

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Enter Feynman slash by dotting a Dirac gamma matrix with a four-vector:

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Contract forms dot products among vectors with repeated indices:

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