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arXiv · 1910.05670

Band-limited Features in the Primordial Power Spectrum Do Not Resolve the Hubble Tension

MiaoXin Liu·Zhiqi Huang
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Abstract

For a standard $\Lambda$CDM universe with a power-law primordial power spectrum, the discrepancy between early- and late-universe measurements of the Hubble constant continued to grow and recently reached $5.3\sigma$. During inflation, local features in the inflationary potential often lead to band-limited features in the primordial power spectrum, hence breaking the power-law assumption in the derivation of the Hubble tension. We investigate whether such inflationary "glitches" can ease the Hubble tension. The recently released \emph{Planck} temperature and polarization data and the 2019 SH0ES+H0LiCOW joint constraint on the Hubble constant are combined to drive a blind Daubechies wavelet signal search in the primordial power spectrum, up to a resolution $\Delta \ln k\sim 0.1$. We find no significant detection of any features beyond power law. With 64 more degrees of freedom injected in the primordial power spectrum, the Hubble tension persists at a $4.9\sigma$ level.

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MiaoXin Liu, Zhiqi Huang. 2019-10-13. Band-limited Features in the Primordial Power Spectrum Do Not Resolve the Hubble Tension. https://doi.org/10.3847/1538-4357%2Fab982e

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