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arXiv · gr-qc/9606006

Wave Packet in Quantum Cosmology and Definition of Semiclassical Time

Yoshiaki Ohkuwa·Tetsuro Kitazoe
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Abstract

We consider a quantum cosmology with a massless background scalar field $\pb$ and adopt a wave packet as the wave function. This wave packet is a superposition of the WKB form wave functions, each of which has a definite momentum of the scalar field $\pb$. In this model it is shown that to trace the formalism of the WKB time is seriously difficult without introducing a complex value for a time. We define a semiclassical real time variable $\tp$ from the phase of the wave packet and calculate it explicitly. We find that, when a quantum matter field $\pq$ is coupled to the system, an approximate Schrödinger equation for $\pq$ holds with respect to $\tp$ in a region where the size $a$ of the universe is large and $|\pb|$ is small.

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Yoshiaki Ohkuwa, Tetsuro Kitazoe. 1996-06-05. Wave Packet in Quantum Cosmology and Definition of Semiclassical Time. https://doi.org/10.1142/s0217751x97000657

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