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Astropy v8.0.0b1

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  • with_H0

with_H0#

astropy.cosmology.units.with_H0(H0=None)[source]#

Convert between quantities with little-h and the equivalent physical units.

Parameters:
H0python:None or Quantity [:ref: ‘frequency’]

The value of the Hubble constant to assume. If a |Quantity|, will assume the quantity is H0. If None (default), use the H0 attribute from |default_cosmology|.

References

For an illuminating discussion on why you may or may not want to use little-h at all, see https://arxiv.org/pdf/1308.4150.pdf

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Updated on 21 May 2026 , built with Sphinx 9.1.0