On Cosmological Isotropy, Quantum Cosmology and the Weyl Curvature Hypothesis

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.

5 pages

Cited by in corpus (19)

• Failure of Standard Conservation Laws at a Classical Change of Signature
• Black holes, cosmological singularities and change of signature
• Actions for signature change
• Comment on "Failure of standard conservation laws at a classical change of signature"
• Reply Comment: Comparison of Approaches to Classical Signature Change
• Cosmological perturbations and classical change of signature
• Signature change induces compactification
• Complex lapse, complex action and path integrals
• An Exploration of the Black Hole Entropy via the Weyl Tensor
• Topology Change and the Propagation of Massless Fields
• Dimensionality, topology, energy, the cosmological constant, and signature change
• Casimir effect in a two dimensional signature changing spacetime
• Casimir stress on parallel plates in de Sitter space with signature change
• Distinguished solutions for discontinuous signature change with weak junction conditions
• Casimir effect for a spherical shell in de Sitter spacetime with signature change
• The trace left by signature-change-induced compactification
• Comments on the multi-dimensional Wheeler-DeWitt equation
• Diffeomorphism algebra of two dimensional free massless scalar field with signature change
• Casimir effect for concentric spheres in de Sitter spacetime with signature change