  Emergent gravity is based on a novel form of the equivalence principle known
as the Darboux theorem or the Moser lemma in symplectic geometry stating that
the electromagnetic force can always be eliminated by a local coordinate
transformation as far as spacetime admits a symplectic structure, in other
words, a microscopic spacetime becomes noncommutative (NC). If gravity emerges
from U(1) gauge theory on NC spacetime, this picture of emergent gravity
suggests a completely new quantization scheme where quantum gravity is defined
by quantizing spacetime itself, leading to a dynamical NC spacetime. Therefore
the quantization of emergent gravity is radically different from the
conventional approach trying to quantize a phase space of metric fields. This
approach for quantum gravity allows a background independent formulation where
spacetime as well as matter fields is equally emergent from a universal vacuum
of quantum gravity.
