Does a tensorial energy-momentum density for gravitation exist?
No tensorial expression for the energy-momentum density of the gravitational field seems to exist in general relativity. Would this be an ineluctable property of nature, or just a limitation of the general-relativistic geometric bias? An analysis of the spin connection shows that the non-tensorial character of the general relativity expressions is due to the fact that they all include the energy-momentum density of the fictitious forces associated to the non-inertiality of the adopted frame--which is non-tensorial by its very nature. Splitting the spin connection in such a way as to separate gravity from inertia, one ends up with teleparallel gravity, where a tensorial expression for the energy-momentum of gravity alone naturally emerges. Like the energy-momentum tensor of any other field in the presence of gravitation, it is conserved only in the covariant sense.