Description
The observational evidence for a local ~200Mpc, underdensity goes back to the 1990's and, like the "Hubble tension", remains unexplained by the standard cosmology. Wong et al (2022, MNRAS, 511, 5742) show that the Local Hole covers >90% of the sky out to ~200Mpc with an ~20% underdensity, consistent with previous independent observations (e.g. Keenan, Barger and Cowie, 2013, ApJ, 775, 62). Here, we demonstrate that a relatively small change to the standard $\Lambda$CDM power spectrum reduces its rejection significance from >30$\sigma$ to <3$\sigma$ and we discuss whether or not such a change can be accommodated in a minimally revised $\Lambda$CDM model. Either way, the Local Hole may halve the significance of the present Hubble Tension. However, caution is still advised since the Local Group seems unnaturally close to the centre of the Local Hole. The more exact this proves to be, the more a fundamentally new (inhomogeneous?) cosmological model might be needed or, at least, the invocation of dramatically strong galaxy evolution at late times (z<0.1), so far unpredicted in $\Lambda$CDM.
