The no-boundary wave function (NBWF) specifies a measure for prediction in
cosmology that selects inflationary histories and remains well behaved for
spatially large or infinite universes. This paper explores the predictions of
the NBWF for linear scalar fluctuations about homogeneous and isotropic
backgrounds in models with a single scalar field moving in a quadratic
potential. We treat both the space-time geometry of the universe and the
observers inhabiting it quantum mechanically. We evaluate top-down
probabilities for local observations that are conditioned on the NBWF and on
part of our data as observers of the universe. For models where the most
probable histories do not have a regime of eternal inflation, the NBWF predicts
homogeneity on large scales, a specific non-Gaussian spectrum of observable
fluctuations, and a small amount of inflation in our past. By contrast, for
models where the dominant histories have a regime of eternal inflation, the
NBWF predicts significant inhomogeneity on scales much larger than the present
horizon, a Gaussian spectrum of observable fluctuations, and a long period of
inflation in our past. The absence or presence of local non-Gaussianity
therefore provides information about the global structure of the universe,
assuming the NBWF.
Beschreibung
The No-Boundary Measure in the Regime of Eternal Inflation
%0 Journal Article
%1 Hartle2010
%A Hartle, James
%A Hawking, S. W.
%A Hertog, Thomas
%D 2010
%K No-Boundary inflation non-gaussian
%T The No-Boundary Measure in the Regime of Eternal Inflation
%U http://arxiv.org/abs/1001.0262
%X The no-boundary wave function (NBWF) specifies a measure for prediction in
cosmology that selects inflationary histories and remains well behaved for
spatially large or infinite universes. This paper explores the predictions of
the NBWF for linear scalar fluctuations about homogeneous and isotropic
backgrounds in models with a single scalar field moving in a quadratic
potential. We treat both the space-time geometry of the universe and the
observers inhabiting it quantum mechanically. We evaluate top-down
probabilities for local observations that are conditioned on the NBWF and on
part of our data as observers of the universe. For models where the most
probable histories do not have a regime of eternal inflation, the NBWF predicts
homogeneity on large scales, a specific non-Gaussian spectrum of observable
fluctuations, and a small amount of inflation in our past. By contrast, for
models where the dominant histories have a regime of eternal inflation, the
NBWF predicts significant inhomogeneity on scales much larger than the present
horizon, a Gaussian spectrum of observable fluctuations, and a long period of
inflation in our past. The absence or presence of local non-Gaussianity
therefore provides information about the global structure of the universe,
assuming the NBWF.
@article{Hartle2010,
abstract = { The no-boundary wave function (NBWF) specifies a measure for prediction in
cosmology that selects inflationary histories and remains well behaved for
spatially large or infinite universes. This paper explores the predictions of
the NBWF for linear scalar fluctuations about homogeneous and isotropic
backgrounds in models with a single scalar field moving in a quadratic
potential. We treat both the space-time geometry of the universe and the
observers inhabiting it quantum mechanically. We evaluate top-down
probabilities for local observations that are conditioned on the NBWF and on
part of our data as observers of the universe. For models where the most
probable histories do not have a regime of eternal inflation, the NBWF predicts
homogeneity on large scales, a specific non-Gaussian spectrum of observable
fluctuations, and a small amount of inflation in our past. By contrast, for
models where the dominant histories have a regime of eternal inflation, the
NBWF predicts significant inhomogeneity on scales much larger than the present
horizon, a Gaussian spectrum of observable fluctuations, and a long period of
inflation in our past. The absence or presence of local non-Gaussianity
therefore provides information about the global structure of the universe,
assuming the NBWF.
},
added-at = {2010-01-05T09:43:19.000+0100},
author = {Hartle, James and Hawking, S. W. and Hertog, Thomas},
biburl = {https://www.bibsonomy.org/bibtex/234c748abd4b272d3522423822058989e/jpschaar},
description = {The No-Boundary Measure in the Regime of Eternal Inflation},
interhash = {0b2c206cfc059d28f42b895253b9bbdc},
intrahash = {34c748abd4b272d3522423822058989e},
keywords = {No-Boundary inflation non-gaussian},
note = {cite arxiv:1001.0262
Comment: 29 pages, 8 figures},
timestamp = {2010-01-05T09:43:19.000+0100},
title = {The No-Boundary Measure in the Regime of Eternal Inflation},
url = {http://arxiv.org/abs/1001.0262},
year = 2010
}