What the small angle CMB really tells us about the curvature of the Universe
Abstract
It is well known that observations of the cosmic microwave background (CMB) are highly sensitive to the spatial curvature of the Universe, k. Here we find that what is in fact being tightly constrained by small angle fluctuations is spatial curvature near the surface of last scattering, and that if we allow k to be a function of position, rather than taking a constant value everywhere, then considerable spatial curvature is permissible within our own locale. This result is of interest for the giant void models that attempt to explain the supernovae observations without Dark Energy. We find such voids to be compatible with the observed small angle CMB, but they must be either very deep (and unnaturally empty) or exist in a positively curved Universe.
 Authors:

 Oxford Astrophysics, Physics, DWB, Keble Road, Oxford, OX1 3RH (United Kingdom)
 Publication Date:
 OSTI Identifier:
 22273195
 Resource Type:
 Journal Article
 Journal Name:
 Journal of Cosmology and Astroparticle Physics
 Additional Journal Information:
 Journal Volume: 2009; Journal Issue: 07; Other Information: Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 14757516
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ASTROPHYSICS; COSMOLOGY; FLUCTUATIONS; NONLUMINOUS MATTER; RELICT RADIATION; SUPERNOVAE; UNIVERSE
Citation Formats
Clifton, Timothy, Ferreira, Pedro G., and Zuntz, Joe. What the small angle CMB really tells us about the curvature of the Universe. United States: N. p., 2009.
Web. doi:10.1088/14757516/2009/07/029.
Clifton, Timothy, Ferreira, Pedro G., & Zuntz, Joe. What the small angle CMB really tells us about the curvature of the Universe. United States. https://doi.org/10.1088/14757516/2009/07/029
Clifton, Timothy, Ferreira, Pedro G., and Zuntz, Joe. Wed .
"What the small angle CMB really tells us about the curvature of the Universe". United States. https://doi.org/10.1088/14757516/2009/07/029.
@article{osti_22273195,
title = {What the small angle CMB really tells us about the curvature of the Universe},
author = {Clifton, Timothy and Ferreira, Pedro G. and Zuntz, Joe},
abstractNote = {It is well known that observations of the cosmic microwave background (CMB) are highly sensitive to the spatial curvature of the Universe, k. Here we find that what is in fact being tightly constrained by small angle fluctuations is spatial curvature near the surface of last scattering, and that if we allow k to be a function of position, rather than taking a constant value everywhere, then considerable spatial curvature is permissible within our own locale. This result is of interest for the giant void models that attempt to explain the supernovae observations without Dark Energy. We find such voids to be compatible with the observed small angle CMB, but they must be either very deep (and unnaturally empty) or exist in a positively curved Universe.},
doi = {10.1088/14757516/2009/07/029},
url = {https://www.osti.gov/biblio/22273195},
journal = {Journal of Cosmology and Astroparticle Physics},
issn = {14757516},
number = 07,
volume = 2009,
place = {United States},
year = {2009},
month = {7}
}