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Holographic Discreteness of Inflationary Perturbations

Craig J. Hogan
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Abstract

The holographic entropy bound is used to estimate the quantum-gravitational discreteness of inflationary perturbations. In the context of scalar inflaton perturbations produced during standard slow-roll inflation, but assuming that horizon-scale perturbations ``freeze out'' in discrete steps separated by one bit of total observable entropy, it is shown that the Hilbert space of a typical horizon-scale inflaton perturbation is equivalent to that of about 10^5 binary spins-- approximately the inverse of the final scalar metric perturbation amplitude, independent of other parameters. Holography thus suggests that in a broad class of fundamental theories, inflationary perturbations carry a limited amount of information (about 10^5 bits per mode) and should therefore display discreteness not predicted by the standard field theory. Some manifestations of this discreteness may be observable in cosmic background anisotropy.

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Craig J. Hogan. 2002-05-27. Holographic Discreteness of Inflationary Perturbations. https://doi.org/10.1103/physrevd.66.023521

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