Yang-Mills Theory in Three Dimensions as Quantum Gravity Theory

We perform the dual transformation of the Yang-Mills theory in d=3 dimensions using the Wilson action on the cubic lattice. The dual lattice is made of tetrahedra triangulating a 3-dimensional curved manifold but embedded into a flat 6-dimensional space (for the SU(2) gauge group). In the continuum limit the theory can be reformulated in terms of 6-component gauge-invariant scalar fields having the meaning of the external coordinates of the dual lattice sites. These 6-component fields induce a metric and a curvature of the 3-dimensional dual colour space. The Yang-Mills theory can be identically rewritten as a quantum gravity theory with the Einstein-Hilbert action but purely imaginary Newton constant, plus a homogeneous `matter' term. Interestingly, the theory can be formulated in a gauge-invariant and local form without explicit colour degrees of freedom.