Principle of covariance

Principle in relativity

In physics, the principle of covariance emphasizes formulating physical laws using only those quantities whose measurements can be unambiguously correlated by observers in different frames of reference. Mathematically, the physical quantities must transform covariantly, that is, under a certain representation of the group of coordinate transformations between admissible frames of reference of the physical theory. This group is referred to as the covariance group.

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