Classical and quantum cosmology with York time

@article{Roser2014ClassicalAQ,
  title={Classical and quantum cosmology with York time},
  author={Philipp Roser and Antony Valentini},
  journal={Classical and Quantum Gravity},
  year={2014},
  volume={31}
}
We consider a solution to the problem of time in quantum gravity by deparameterization of the ADM action in terms of York time, a parameter proportional to the extrinsic curvature of a spatial hypersurface. We study a minisuperspace model together with a homogeneous scalar field, for which we can solve the Hamiltonian constraint exactly and arrive at an explicit expression for the physical (non-vanishing) Hamiltonian. The scale factor and associated momentum cease to be dynamical variables… 
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