  We argue that the structure general relativity (GR) as a theory of affine
defects is deeper than the standard interpretation as a metric theory of
gravitation. Einstein-Cartan theory (EC), with its inhomogenous affine
symmetry, should be the standard-bearer for GR-like theories. A discrete affine
interpretation of EC (and gauge theory) yields topological definitions of
momentum and spin (and Yang Mills current), and their conservation laws become
discrete topological identities. Considerations from quantum theory provide
evidence that discrete affine defects are the physical foundation for
gravitation.
