Editing General covariance (section)

{{Short description|Principle stating that physical laws are the same in all coordinate systems}}
In [[theoretical physics]], '''general covariance''', also known as '''[[diffeomorphism]] covariance''' or '''general invariance''', consists of the [[Invariant (physics)|invariance]] of the ''form'' of [[physical law]]s under arbitrary [[Derivative|differentiable]] [[coordinate transformation]]s. The essential idea is that coordinates do not exist ''a&nbsp;priori'' in nature, but are only artifices used in describing nature, and hence should play no role in the formulation of fundamental physical laws. While this concept is exhibited by [[general relativity]], which describes the dynamics of [[spacetime]], one should not expect it to hold in less fundamental theories. For matter fields taken to exist independently of the background, it is almost never the case that their [[equations of motion]] will take the same form in curved space that they do in flat space.