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arXiv · 2401.06887

Time problem in primordial perturbations

Alice Boldrin·Przemysław Małkiewicz·Patrick Peter
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Abstract

We study the non-unitary relation between quantum gravitational models defined using different internal times. We show that despite the non-unitarity, it is possible to provide a prescription for making unambiguous, though restricted, physical predictions independent of specific clocks. To illustrate this result, we employ a model of quantum gravitational waves in a quantum Friedmann universe.

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Alice Boldrin, Przemysław Małkiewicz, Patrick Peter. 2024-01-12. Time problem in primordial perturbations. https://doi.org/10.1103/physrevd.109.106005

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