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Updated: Jun 23, 2025

Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Improved Planck Constraints on Axionlike Early Dark Energy as a Resolution of the Hubble Tension
George Efstathiou1, Erik Rosenberg1,2, Vivian Poulin3
1Kavli Institute for Cosmology and Institute of Astronomy, Madingley Road, Cambridge CB2 0HA, United Kingdom.
Abstract:
Axionlike early dark energy (EDE) as an extension to Λ cold dark matter (ΛCDM) has been proposed as a possible solution to the "Hubble tension." We revisit this model using a new cosmic microwave background (CMB) temperature and polarization likelihood constructed from the Planck NPIPE data release. In a Bayesian analysis, we find that the maximum fractional contribution of EDE to the total energy density is f_{EDE}<0.061 (without SH0ES) over the redshift range z∈[10^{3},10^{4}] and that the Hubble constant is constrained to lie within the range 66.9
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