# 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}
}
• Published 11 September 2018
• Mathematics, Physics
• Annales Henri Poincaré
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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