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Classical Spacetime from Quantum Gravity

Sang Pyo Kim
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Abstract

We show how classical spacetime emerges from quantum gravity through the study of a quantum FRW cosmological model coupled to a free massive scalar field using a new asymptotic expansion method of the Wheeler-DeWitt equation. It is shown that the coherent states of the nonadiabatic basis of a particular generalized invariant give rise to the quantum back reaction of matter field proportional to classical energy and the Einstein-Hamilton-Jacobi with matter becomes equivalent to the classical Einstein equation.

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Sang Pyo Kim. 1996-09-02. Classical Spacetime from Quantum Gravity. https://doi.org/10.1088/0264-9381%2F13%2F6%2F011

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