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arXiv · 1901.04492

A Quantum Complete Prelude to Inflation

Stefan Hofmann·Marc Schneider·Maximilian Urban
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Abstract

It is shown that the inflationary paradigm admits quantum complete extensions of space-time. The extended inflationary spacetimes still have geodesic borders, but quantum fields are prohibited from migrating across these borders by their evolution semigroups. The geodesic singularities lurking across the borders lack a physical description because the evolution semigroups give vanishing probabilistic support to quantum fields for populating regions bordering on these singularities. As an example, anisotropic Bianchi type-I cosmologies are shown to be quantum complete preludes to inflation. They admit Kasner-like geometries close to their geodesic borders. Quantum fields enjoy a contractive evolution in these asymptotic regions and ultimately become free. As a consequence, quantum probes cannot migrate across the geodesic border of Bianchi type-I cosmologies.

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Stefan Hofmann, Marc Schneider, Maximilian Urban. 2019-01-14. A Quantum Complete Prelude to Inflation. https://doi.org/10.1103/physrevd.99.065012

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