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arXiv · gr-qc/9807023

Loss of Quantum Coherence and Positivity of Energy Density in Semiclassical Quantum Gravity

Sang Pyo Kim·Kwang-Sup Soh
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Abstract

In the semiclassical quantum gravity derived from the Wheeler-DeWitt equation, the energy density of a matter field loses quantum coherence due to the induced gauge potential from the parametric interaction with gravity in a non-static spacetime. It is further shown that the energy density takes only positive values and makes superposition principle hold true. By studying a minimal massive scalar field in a FRW spacetime background, we illustrate the positivity of energy density and obtain the classical Hamiltonian of a complex field from the energy density in coherent states.

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Sang Pyo Kim, Kwang-Sup Soh. 1998-09-04. Loss of Quantum Coherence and Positivity of Energy Density in Semiclassical Quantum Gravity. https://arxiv.org/abs/gr-qc/9807023

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