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Dynamical Properties of Euclidean Solutions in a Multidimensional Cosmological Model

Hirotaka Ochiai·Katsuhiko Sato
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Abstract

In the framework of the Hartle-Hawking no-boundary proposal, we investigated quantum creation of the multidimensional universe with a cosmological constant ($Λ$) but without matter fields. We have found that the classical solutions of the Euclidean Einstein equations in this model have ``quasi-attractors'', i.e., most trajectories on the a-b plane, where a and b are the scale factors of external and internal spaces, go around a point. It is presumed that the wave function of the universe has a hump near this quasi-attractor point. In the case that both the curvatures of external and internal spaces are positive, and $Λ>0$, there exist Lorentzian solutions which start near the quasi-attractor, the internal space remains microscopic, and the external space evolves into our macroscopic universe.

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Hirotaka Ochiai, Katsuhiko Sato. 2000-07-22. Dynamical Properties of Euclidean Solutions in a Multidimensional Cosmological Model. https://doi.org/10.1143/ptp.103.893

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