We are at an interesting juncture in cosmology. With new methods and technology, the accuracy in measurement of the Hubble constant has vastly improved, but a recent tension has arisen that is either signaling new physics or as-yet unrecognized uncertainties.
@article{arxiv.1706.02739,
title = {Cosmology at at Crossroads: Tension with the Hubble Constant},
author = {Wendy L. Freedman},
journal= {arXiv preprint arXiv:1706.02739},
year = {2017}
}
Comments
Invited commentary for Nature Astronomy; 10 pages, 2 figures