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arXiv · 0706.3908

Measuring the Expansion of the Universe Through Changes in the CMB Photosphere

S. Lange·L. Page
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Abstract

The expansion of the universe may be observed in ``realtime'' by measuring changes in the patterns of the anisotropy in the CMB. As the universe ages, the surface of decoupling--or the CMB photosphere--moves away from us and samples a different gravitational landscape. The response of the CMB to this new landscape results in a different pattern than we observe today. The largest change occurs at l~900. We show that with an array of detectors that we may envision having in a couple of decades, one can in principle measure the change in the anisotropy with two high precision measurements separated by a century.

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S. Lange, L. Page. 2007-06-26. Measuring the Expansion of the Universe Through Changes in the CMB Photosphere. https://doi.org/10.1086/523097

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