The Hubble Constant appears to be a function only of distance, but time itself is a function of location in space and nearby matter, so that the Hubble Constant is then a functional (a function of a function). Because the Hubble “constant” is a functional of both space and time, 3-dimensional space expands more slowly near matter so that the expansion of 3-space is inhomogeneous, contrary to the usual assumption of homogeneity.
The pdf is available here: https://www.gemarsh.com/wp-content/uploads/Inhomogeneous-3-space-expansion-rate.pdf
Non-Homogeneous 3-Space Expansion