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Nonsingular instantons for the creation of open universes

Pedro F. Gonzalez-Diaz
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Abstract

We show that the instability of the singular Vilenkin instanton describing the creation of an open universe can be avoided using, instead of a minimally coupled scalar field, an axionic massless scalar field which gives rise to the Giddings-Strominger instanton. However, if we replace the singularity of the Hawking Turok instanton for an axionic wormhole some interpretational and technical difficulties would appear which can be overcome by introducing a positive cosmological constant in the action. This would make the instanton finite and free constant in the action. This would make the instanton finite and free from any instabilities.

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BibTeXRIS

Pedro F. Gonzalez-Diaz. 1998-10-27. Nonsingular instantons for the creation of open universes. https://doi.org/10.1103/physrevd.59.043509

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