
We review recent literature on the connection between quantum entanglement and cosmology, with an emphasis on the context of expanding universes. We discuss recent theoretical results reporting on the production of entanglement in quantum fields due to the expansion of the underlying spacetime. We explore how these results are affected by the statistics of the field (bosonic or fermionic), the type of expansion (de Sitter or asymptotically stationary), and the coupling to spacetime curvature (conformal or minimal). We then consider the extraction of entanglement from a quantum field by coupling to local detectors and how this procedure can be used to distinguish curvature from heating by their entanglement signature. We review the role played by quantum fluctuations in the early universe in nucleating the formation of galaxies and other cosmic structures through their conversion into classical density anisotropies during and after inflation. We report on current literature attempting to account for this transition in a rigorous way and discuss the importance of entanglement and decoherence in this process. We conclude with some prospects for further theoretical and experimental research in this area. These include extensions of current theoretical efforts, possible future observational pursuits, and experimental analogues that emulate these cosmic effects in a laboratory setting.
23 pages, 2 figures. v2 Added journal reference and minor changes to match the published version
Quantum Physics, Cosmology and Nongalactic Astrophysics (astro-ph.CO), FOS: Physical sciences, General Relativity and Quantum Cosmology (gr-qc), Quantum Physics (quant-ph), General Relativity and Quantum Cosmology, Astrophysics - Cosmology and Nongalactic Astrophysics
Quantum Physics, Cosmology and Nongalactic Astrophysics (astro-ph.CO), FOS: Physical sciences, General Relativity and Quantum Cosmology (gr-qc), Quantum Physics (quant-ph), General Relativity and Quantum Cosmology, Astrophysics - Cosmology and Nongalactic Astrophysics
| citations This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically). | 116 | |
| popularity This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network. | Top 1% | |
| influence This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically). | Top 10% | |
| impulse This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network. | Top 10% |
