Entanglement in holographic dark energy models

R. Horvat

doi:10.1016/j.physletb.2010.09.014

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arXiv · 1003.4363

Entanglement in holographic dark energy models

R. Horvat

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Abstract

We study a process of equilibration of holographic dark energy (HDE) with the cosmic horizon around the dark-energy dominated epoch. This process is characterized by a huge amount of information conveyed across the horizon, filling thereby a large gap in entropy between the system on the brink of experiencing a sudden collapse to a black hole and the black hole itself. At the same time, even in the absence of interaction between dark matter and dark energy, such a process marks a strong jump in the entanglement entropy, measuring the quantum-mechanical correlations between the horizon and its interior. Although the effective quantum field theory (QFT) with a peculiar relationship between the UV and IR cutoffs, a framework underlying all HDE models, may formally account for such a huge shift in the number of distinct quantum states, we show that the scope of such a framework becomes tremendously restricted, devoiding it virtually any application in other cosmological epochs or particle-physics phenomena. The problem of negative entropies for the non-phantom stuff is also discussed.

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R. Horvat. 2010-09-06. Entanglement in holographic dark energy models. https://doi.org/10.1016/j.physletb.2010.09.014

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