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arXiv · 2503.18499

From a quantum world to our classical Universe

Claus Kiefer
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Abstract

Modern cosmological theories invoke the idea that all structure in the Universe originates from quantum fluctuations. Understanding the quantum-to-classical transition for these fluctuations is of central importance not only for the foundations of quantum theory, but also for observational astronomy. In my contribution, I review the essential features of this transition, emphasizing in particular the role of Alexei Starobinsky.

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Claus Kiefer. 2025-03-24. From a quantum world to our classical Universe. https://arxiv.org/abs/2503.18499

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