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Cosmology at a crossroads


A Correction to this article was published on 26 May 2017

We are at an interesting juncture in cosmology. Despite vast improvements in the measurement accuracy of the Hubble constant, a recent tension has arisen that is either signalling new physics or as-yet unrecognized uncertainties.

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Figure 1: The current tension in the determination of H0.
Figure 2: The tip of the red giant branch for measuring distances.


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Correspondence to Wendy L. Freedman.

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Freedman, W. Cosmology at a crossroads. Nat Astron 1, 0121 (2017).

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