Einstein’s theory is gradient-based in that it explains gravity not as a force but as curvature of spacetime

 Einstein’s theory is gradient-based in that it explains gravity not as a force but as curvature of spacetime. In general relativity, the curvature tensor arises from the second derivative (gradient) of the metric tensor 

$g_{\mu\nu}$, forming the gravitational field. In special relativity, conservation laws $\nabla_\mu T^{\mu\nu}=0$ show that all physical changes are expressed as gradients. Philosophically, time, space, and mass are not absolute entities but relational gradients. Thus, Einstein’s theory presents the universe as a structure of relational gradients.