# 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…

## 9 Citations

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We consider solutions of the semi-classical Einstein–Klein–Gordon system with a cosmological constant $$\Lambda \in \mathbb {R}$$
Λ
∈
R
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A semiclassical singularity theorem

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Quantum fields do not satisfy the pointwise energy conditions that are assumed in the original singularity theorems of Penrose and Hawking. Accordingly, semiclassical quantum gravity lies outside…

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