Affine-Goldstone/Quartet-Metric Gravity and Beyond

Abstract

As a group—theoretic foundation of gravity, it is considered an affine-Goldstone nonlinear model based upon the nonlinear realization of the global affine symmetry spontaneously broken at the Planck scale to the Poincaré symmetry. It is shown that below this scale the model justifies and elaborates an earlier introduced effective field theory of the quartet-metric gravity incorporating the gravitational dark substances emerging in addition to the tensor graviton. The prospects for subsequent going beyond the nonlinear model above the Planck scale are indicated.