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arXiv · hep-th/0611277

Exact spectrum of scalar field perturbations in a radiation deformed closed de Sitter universe

Sash Sarangi·Koenraad Schalm·Gary Shiu·Jan Pieter van der Schaar
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Abstract

We observe that the equation of motion for a free scalar field in a closed universe with radiation and a positive cosmological constant is given by Lamé's equation. Computing the exact power spectrum of scalar field perturbations, the presence of both curvature and radiation produces a red tilt weakly dependent on the amount of radiation.

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Sash Sarangi, Koenraad Schalm, Gary Shiu, Jan Pieter van der Schaar. 2006-11-25. Exact spectrum of scalar field perturbations in a radiation deformed closed de Sitter universe. https://doi.org/10.1088/1475-7516%2F2007%2F03%2F002

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