# Cosmology with quantum matter and a classical gravitational field: the approach of configuration-space ensembles

@article{Reginatto2009CosmologyWQ, title={Cosmology with quantum matter and a classical gravitational field: the approach of configuration-space ensembles}, author={Marcel Reginatto}, journal={Journal of Physics: Conference Series}, year={2009}, volume={442}, pages={012009} }

I consider the formulation of hybrid cosmological models that consists of a classical gravitational field interacting with a quantized massive scalar field in the formalism of ensembles on configuration space. This is a viable approach that provides an alternative to semiclassical gravity. I discuss a particular, highly nonclassical solution in two approximations, minisuperspace and spherically-symmetric midisuperspace. In both cases, the coupling of the quantum scalar field and classical…

## 6 Citations

### Coupling of Quantum Fields to Classical Gravity

- Physics
- 2016

We consider ensembles on configuration space that consist of quantum fields which interact with and are the source of a classical gravitational field. These are hybrid systems where gravity remains…

### Entanglement of quantum fields via classical gravity

- Physics
- 2018

We consider the coupling of quantum fields to classical gravity in the formalism of ensembles on configuration space, a model that allows a consistent formulation of interacting classical and quantum…

### Ensembles of Classical Gravitational Fields

- Physics
- 2016

We define ensembles on configuration space for classical gravitational fields that obey the Einstein equations. Our starting point is the Hamilton–Jacobi formulation of general relativity. After a…

### On two recent proposals for witnessing nonclassical gravity

- Physics
- 2017

It is shown that the claim that quantum systems cannot become entangled via a classical intermediary is also valid for mean-field models, but that it is contradicted by explicit counterexamples based on the configuration-ensemble model.

### Performance of fourth and sixth-order commutator-free Magnus expansion integrators for Ehrenfest dynamics

- Physics, Computer ScienceComput. Math. Methods
- 2021

### Entangling quantum fields via a classical gravitational interaction

- PhysicsJournal of Physics: Conference Series
- 2019

We consider the coupling of quantum fields to classical gravity in the formalism of ensembles on configuration space, a model that allows a consistent formulation of interacting classical and quantum…

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