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On Cosmological Isotropy, Quantum Cosmology and the Weyl Curvature Hypothesis

Sean A. Hayward
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Abstract

The increasing entropy, large-scale isotropy and approximate flatness of the universe are considered in the context of signature change, which is a classical model of quantum tunnelling in quantum cosmology. The signature change hypothesis implies an initial inflationary epoch, the magnetic half of the Weyl curvature hypothesis, and a close analogue of the conformal singularity hypothesis. Adding the electric half of the Weyl curvature hypothesis yields, for a perfect fluid, only homogeneous and isotropic cosmologies. In the cosmological-constant case, the unique solution is the Vilenkin tunnelling solution, which gives a de Sitter cosmology.

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Sean A. Hayward. 1992-12-10. On Cosmological Isotropy, Quantum Cosmology and the Weyl Curvature Hypothesis. https://doi.org/10.1088/0264-9381%2F10%2F1%2F002

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