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The No-Boundary Wave Function and the Duration of the Inflationary Period

A. Lukas
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Abstract

For the simplest minisuperspace model based on a homogeneous, isotropic metric and a minimally coupled scalar field we derive analytic expressions for the caustic which separates Euklidean and Minkowskian region and its breakdown value $\p_*$. This value represents the prediction of the no-boundary wave function for the scalar field at the beginning of inflation. We use our results to search for inflationary models which can render the no-boundary wave function consistent with the requirement of a sufficiently long inflationary period.

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A. Lukas. 1994-09-07. The No-Boundary Wave Function and the Duration of the Inflationary Period. https://doi.org/10.1016/0370-2693(94)01693-7

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