# Linear stability of semiclassical theories of gravity

@inproceedings{Meda2022LinearSO, title={Linear stability of semiclassical theories of gravity}, author={Paolo Meda and Nicola Pinamonti}, year={2022} }

The linearization of semiclassical theories of gravity is investigated in a toy model, consisting of a quantum scalar field in interaction with a second classical scalar field which plays the role of a classical background. This toy model mimics also the evolution induced by semiclassical Einstein equations, such as the one which describes the early universe in the cosmological case. The equations governing the dynamics of linear perturbations around simple exact solutions of this toy model are…

## 2 Citations

### Cosmological de Sitter Solutions of the Semiclassical Einstein Equation

- Physics
- 2022

Exponentially expanding space-times play a central role in contemporary cosmology, most importantly in the theory of inflation and in the Dark Energy driven expansion in the late universe. In this…

### On the initial value problem for semiclassical gravity without and with quantum state collapses

- Physics, Mathematics
- 2022

Semiclassical gravity is the theory in which the classical Einstein tensor of a spacetime is coupled to quantum matter ﬁelds propagating on the spacetime via the expectation value of their…

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