I have suggested that Einstein's gravity/curvature is a post-inflation macro-quantum coherent emergent collective effect in the Higgs-Goldstone vacuum superconductor, an elastic-plastic analog of superflow in liquid helium below the Lambda point ~ gradient of the macro-quantum coherent helium ground state with spontaneous broken non-electromagnetic U1 symmetry.
Here is another interesting approach with the SU2 weak group not the SU3 strong group. It has a kind of twistor nonlocality and non-commutative geometry.
He's got a torsion field there.
I think there is an inconsistency in his math. Can't have d^x^u/ds = constant when the antisymmetric torsion tensor =/= 0.
i.e. the torsion field tensor makes a real force that cannot be eliminated because it is a tensor under the original general coordinate transformations unlike the Christoffel symbol (of Newton's G-force).
GRAVITATIONAL AND ELECTROWEAK UNIFICATION BY REPLACING DIFFEOMORPHISMS WITH LARGER GROUP
DAVE PANDRES, JR.
Abstract. The covariance group for general relativity, the diffeomor-
phisms, is replaced by a group of coordinate transformations which con-
tains the diffeomorphisms as a proper subgroup. The larger group is
defined by the assumption that all observers will agree whether any given
quantity is conserved. Alternatively, and equivalently, it is defined by the
assumption that all observers will agree that the general relativistic wave
equation describes the propagation of light. Thus, the group replacement
is analogous to the replacement of the Lorentz group by the diffeomor-
phisms that led Einstein from special relativity to general relativity, and
is also consistent with the assumption of constant light velocity that led
him to special relativity. The enlarged covariance group leads to a non-
commutative geometry based not on a manifold, but on a nonlocal space
in which paths, rather than points, are the most primitive invariant enti-
ties. This yields a theory which unifies the gravitational and electroweak
interactions. The theory contains no adjustable parameters, such as those
that are chosen arbitrarily in the standard model.