Abstract :
A minimal Lorentz gauge gravity model with R2-type Lagrangian is proposed. In the absence of torsion the model admits a topological phase with unfixed metric. The model possesses a minimal set of dynamical degrees of freedom for the torsion. Remarkably, the torsion has the same number of dynamical of-shell degrees of freedom as the metric tensor. We trace an analogy between the structure of the quantum chromodynamics and the structure of possible theory of quantum gravity.