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Unitarity Condition on Quantum Fields in Semiclassical Gravity

Sang Pyo Kim
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Abstract

The condition for the unitarity of a quantum field is investigated in semiclassical gravity from the Wheeler-DeWitt equation. It is found that the quantum field preserves unitarity asymptotically in the Lorentzian universe, but does not preserve unitarity completely in the Euclidean universe. In particular we obtain a very simple matter field equation in the basis of the generalized invariant of the matter field Hamiltonian whose asymptotic solution is found explicitly.

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Sang Pyo Kim. 1995-11-13. Unitarity Condition on Quantum Fields in Semiclassical Gravity. https://doi.org/10.1016/0375-9601(95)00584-p

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