# Can other fundamental forces bend spacetime?

I was wondering what makes gravity so special that it bends spacetime? and if it is part of the four-fundamental forces, why or why cant the other forces bend the time space continuum?

According to General Relativity the gravitational field is equivalent to the geometric properties of spacetime. This geometric properties are given by the curvature tensor which is determined by the Einstein's field equations (EFE)$$R_{\mu\nu} - {\textstyle 1 \over 2}R\,g_{\mu\nu} = {8 \pi G \over c^4} T_{\mu\nu}\,$$
A bending of space-time can be observed through the study of the metric describing it, specifically through the Riemann curvature tensor. Based on the current knowledge, space-time is assumed to be a 4-dimensional manifold which is locally modelled on flat Minkowski space-time. General relativity relates the geometry of space-time, that is the metric $g$, with the energy/matter density. It turns out that matter effectively curves space-time, but other forces, despite contributing to the stress-energy tensor, lead to some traceless contribution to the theory. That's how current theories are formulated these days and as far as I know there is a good agreement with observations.