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The Stability of the Minisuperspace

Atushi Ishikawa·Toshiki Isse
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Abstract

The stability of the minisuperspace model of the early universe is studied by solving the Wheeler-DeWitt equation numerically. We consider a system of Einstein gravity with a scalar field. When we solve the Wheeler-DeWitt equation, we pick up some inhomogeneous wave modes from the infinite number of modes adequately: degrees of freedom of the superspace are restricted to a finite one. We show that the minisuperspace is stable when a scale factor ($a$) of the universe is larger than a few times of the Planck length, while it becomes unstable when $a$ is comparable to the Planck length.

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Atushi Ishikawa, Toshiki Isse. 1993-08-05. The Stability of the Minisuperspace. https://doi.org/10.1142/s0217732393003834

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