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arXiv · 2412.02444

Entanglement and decoherence in cosmology and in analogue gravity experiments

Amaury Micheli
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Abstract

This thesis is dedicated to analysing the generation and destruction of quantum correlations in the context of inflationary cosmology and an experiment of 'analogue' preheating. Inflation is a phase of accelerated expansion of the Universe, preceding the so-called Standard Model of Big Bang cosmology, introduced to solve some shortcomings of this model. It also provides a mechanism for the emergence of primordial inhomogeneities by amplification of initial quantum fluctuations. Inflation is followed by a 'reheating' period, in which most particles are expected to be generated and reach thermal equilibrium, setting the stage for the standard Big Bang of cosmology. During a 'preheating' period, this creation proceeds partly by parametric excitation of resonant modes of the matter fields initially in their vacuum, a genuine quantum process. The physics of both situations, inflation and preheating, is that of a strong classical field acting on a quantum field to produce entangled (quasi-)particles. When the classical source is the space-time metric itself, as in inflation, we are in the framework of Quantum Field Theory in Curved Space-time (QFTCS). The evolution of the generated quantum correlations is the topic of this PhD.

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Amaury Micheli. 2024-12-03. Entanglement and decoherence in cosmology and in analogue gravity experiments. https://arxiv.org/abs/2412.02444

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