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arXiv · 2501.15704

Uncertainties in the Hubble Constant from Peculiar Velocities

Amber M. Hollinger·Michael J. Hudson
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Abstract

Recent measurements of the Hubble constant using type Ia supernovae explicitly correct for their estimated peculiar velocities using the 2M++ reconstruction of the local density field. The amount of uncertainty from this reconstruction procedure has thus far been unquantified. To rectify this, we use mock universe realisations of the 2M++ catalogue and generate predicted peculiar velocities using the same method as the predictions that are used to correct for the Pantheon+ catalogue. We find that the method yields uncertainties of 0.3 km/s/Mpc and hence subdominant to the total uncertainty in H0.

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Amber M. Hollinger, Michael J. Hudson. 2025-01-26. Uncertainties in the Hubble Constant from Peculiar Velocities. https://arxiv.org/abs/2501.15704

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