The Cosmological Semiclassical Einstein Equation as an Infinite-Dimensional Dynamical System

@article{Gottschalk2018TheCS,
  title={The Cosmological Semiclassical Einstein Equation as an Infinite-Dimensional Dynamical System},
  author={Hanno Gottschalk and Daniel Siemssen},
  journal={Annales Henri Poincar{\'e}},
  year={2018}
}
We develop a comprehensive framework in which the existence of solutions to the semiclassical Einstein equation (SCE) in cosmological spacetimes is shown. Different from previous work on this subject, we do not restrict to the conformally coupled scalar field and we admit the full renormalization freedom. Based on a regularization procedure, which utilizes homogeneous distributions and is equivalent to Hadamard point splitting, we obtain a reformulation of the evolution of the quantum state as… 
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Methods Citations
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11 Citations

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TLDR
It is suggested that if traversable wormholes do exist as solutions to the semiclassical equations, they cannot be macroscopic but must be ``Planck scale'', in agreement with conclusions drawn by Ford and Roman from entirely independent arguments.
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