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arXiv · 1907.03776

Matter-Geometry entanglement in quantum cosmology

Viqar Husain·Suprit Singh
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Abstract

We present a study of the evolution of entanglement entropy of matter and geometry in quantum cosmology. For a variety of Gaussian initial states and their linear combinations, and with evolution defined with respect to a relational time, we show numerically that (i) entanglement entropy increases rapidly at very early times, and subsequently saturates to a constant non-zero value, and (ii) that the saturation value of this entropy is a linear function of the energy associated to the quantum state: $S_{\text{ent}}^\psi = \gamma \langle \hat{H} \rangle_\psi$. These results suggest a remnant of quantum entanglement in the macroscopic Universe from the era of the Big Bang, independent of the initial state parameters, and a "First Law" associated with matter-gravity entanglement entropy in quantum gravity.

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Viqar Husain, Suprit Singh. 2019-07-08. Matter-Geometry entanglement in quantum cosmology. https://doi.org/10.1088/1361-6382%2Fab9d97

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