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arXiv · astro-ph/9608106

Normalization of modes in an open universe

Juan Garcia-Bellido·Andrew R Liddle·David H Lyth·David Wands
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Abstract

We discuss the appropriate normalization of modes required to generate a homogeneous random field in an open Friedmann-Robertson-Walker universe. We consider scalar random fields and certain tensor random fields that can be obtained by covariantly differentiating a scalar. Modes of interest fall into three categories: the familiar sub-curvature modes, the more recently discussed super-curvature modes, and a set of discrete modes with positive eigenvalues which can be used to generate homogeneous tensor random fields even though the underlying scalar field is not homogeneous. A particular example of the last case which has been discussed in the literature is the bubble wall fluctuation in open inflationary universes.

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Juan Garcia-Bellido, Andrew R Liddle, David H Lyth, David Wands. 1996-11-12. Normalization of modes in an open universe. https://doi.org/10.1103/physrevd.55.4596

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