Spatial curvature sensitivity to local H0 from the Cepheid distance ladder

Over the last few years, low- and high-redshift observations set off a tension in measurement of present-day expansion rate, $H_0$. Adding to riddle, observational data from Planck mission point $3.4\sigma$ evidence for closed universe, further challenging $\Lambda$CDM concordance model cosmology. Recently, direct-observational test has been proposed discriminate effects spatial curvature cosmological model. The is based on fundamental distance--flux--redshift relation luminosity distance modulus, $\Delta \mu$. We reexamine outcomes this show that achieving required \mu$ sensitivity among models materially far more than previously thought. Armed with supernova type Ia (SN Ia) data, calibrated using Cepheid measured distances, we apply archetypal spatially non-flat ameliorate $H_0$ $3\sigma$ contour predicted by these overlaps 68\% CL SN residuals respect $\Lambda$CDM. This implies remains insensitive local measurements ladder.