What theory of spacetime was formulated by Albert Einstein?
Albert Einstein in physics at the time—was superfluous. In his paper on mass–energy equivalence, Einstein produced "E" = "mc" as a consequence of his special relativity equations. Einstein's 1905 work on relativity remained controversial for many years, but was accepted by leading physicists, starting with Max Planck. Einstein originally framed special relativity in terms of kinematics (the study of moving bodies). In 1908, Hermann Minkowski reinterpreted special relativity in geometric terms as a theory of spacetime. Einstein adopted Minkowski's formalism in his 1915 general theory of relativity. General relativity (GR) is a theory of gravitation that was developed by Einstein between 1907
Einstein–Cartan theory avoidance of a gravitational singularity at the beginning of the universe. The theory is considered viable and remains an active topic in the physics community. The Einstein field equations of general relativity can be derived by postulating the Einstein–Hilbert action to be the true action of spacetime and then varying that action with respect to the metric tensor. The field equations of Einstein–Cartan theory come from exactly the same approach, except that a general asymmetric affine connection is assumed rather than the symmetric Levi-Civita connection (i.e., spacetime is assumed to have torsion in addition to curvature), and then the metric