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The Role of Time in Physical Cosmology

D. S. Salopek
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Abstract

Recent advances in observational cosmology are changing the way we view the nature of time. In general relativity, the freedom in choosing a time hypersurface has hampered the implementation of the theory. Fortunately, Hamilton-Jacobi theory enables one to describe all time hypersurfaces on an equal footing. Using an expansion in powers of the spatial curvature, one may solve for the wavefunctional in a semiclassical approximation. In this way, one may readily compare predictions of various inflation models with observations of microwave background anisotropies and galaxy clustering.

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D. S. Salopek. 1995-10-10. The Role of Time in Physical Cosmology. https://arxiv.org/abs/astro-ph/9510059

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