D'Alembertian operator
From Wikipedia, the free encyclopedia.

In special relativity and electromagnetism and wave theory, the d'Alembertian operator is defined by:

Note: Some articles/textbooks use the opposite sign convention.

As with other operators in special relativity, the d'Alembertian operator is invariant under a Lorentz transformation.

The original article can be found at: http://en.wikipedia.org/wiki/D'Alembertian_operator.
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