  The Einstein--Cartan Theory (ECT) of gravity is a modification of General
Relativity Theory (GRT), allowing space-time to have torsion, in addition to
curvature, and relating torsion to the density of intrinsic angular momentum.
This modification was put forward in 1922 by Elie Cartan, before the discovery
of spin. Cartan was influenced by the work of the Cosserat brothers (1909), who
considered besides an (asymmetric) force stress tensor also a moments stress
tensor in a suitably generalized continuous medium.
