A Lorentz tensor is any quantity which transforms like a tensor under the homogeneous Lorentz transformation.
See also
Lorentz Group, Lorentz Transformation
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References
Weinberg, S. Gravitation and Cosmology: Principles and Applications of the General Theory of Relativity. New York: Wiley, 1972.
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Cite this as:
Weisstein, Eric W. "Lorentz Tensor." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/LorentzTensor.html