Corpus ID: 237503225

Dark Energy at early times and ACT: a larger Hubble constant without late-time priors

  title={Dark Energy at early times and ACT: a larger Hubble constant without late-time priors},
  author={Vivian Poulin and Tristan L. Smith and Alexa Bartlett},
Recent observations using the Atacama Cosmology Telescope (ACT) have provided ground-based cosmic microwave background (CMB) maps with higher angular resolution than the Planck satellite. These have the potential to put interesting constraints on models resolving the ‘Hubble tension’. In this paper we fit two models of Early Dark Energy (EDE) (an increase in the expansion rate around matter/radiation equality) to the combination of ACT data with large-scale measurements of the CMB either from… Expand
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