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To derive loop quantum cosmology from loop quantum gravity, I apply the modelgiven in \cite{lin1} to a system with coupled gravitational and matter fields.The matter sector consists of a scalar field $phi$ serving as a cosmologicalclock, and other fields ${psi}$ providing physical spatial coordinates andframes. The physical Hilbert space of the model is constructed from thekinematical Hilbert space of loop quantum gravity, and the local observables inthe physical Hilbert space are constructed using the matter coordinates andframes. A specific coherent physical state is then chosen, whose expectationvalues of the local observables give rise to homogeneous, isotropic andspatially flat gravitational and $phi$ fields at a late clock time. Theequations governing these fields may be derived using the symmetry of thephysical Hilbert space. When the matter back reactions from ${psi}$ arenegligible, the result gives a specific loop quantum cosmological model in the$O(hbar^0)$ approximation, with calculable higher order corrections.

Emergence of Loop Quantum Cosmology from Loop Quantum Gravity: Lowest Order in h