Fuzzy dark matter and the Hubble constant strong gravitational lensing measurement

Fuzzy dark matter can form cored density distributions, called solitons, at the center of galaxies. Such cores can be viewed as approximate mass sheets, and can affect the time delay cosmography Hubble constant (H0) measurement via the mass sheet degeneracy. We show that a subdominant component of fuzzy dark matter can yield a 10 percent shift in the inferred H0, if the particle mass is order 10^-25 eV. The sensitivity of time delays on such cores (difficult to probe otherwise) may give a further probe in constraining the fuzzy dark matter scenario, if an H0 prior is assumed.