Hubble trouble: A new measure of the universal expansion using lensed supernovae

Modern cosmology can explain the evolution of the Universe using only six parameters, typically determined with sub-percent accuracy. They include the amount of dark matter, necessary for forming the structures observed, and the dark energy density, responsible for the accelerated universal expansion. However, the arguably most fundamental parameter, the Hubble constant giving the current universal expansion rate, hints at a possible crack in the model: Distance measurements at z < 0.1 give h = 0.73 ± 0.01, whereas the distance to the CMB at z ≈ 1000 gives h = 0.674 ± 0.005. This >5σ Hubble tension stands as one of cosmology´s most compelling debates, as it not only introduces a 10% uncertainty in the size and age of the Universe, but also hints at the existence of undiscovered physical phenomena.This project advocates a new use of lensed supernovae at intermediate z to refine our measurement of h. The method not only promises to bridge the gap between the conflicting low and high redshift estimates, but also offers a unique vantage point to evaluate whether systematic effects or unaccounted-for physics predominantly contribute to the observed tension. In addition, the supernovae will be used as a novel probe into the nature of dark matter and deviations from general relativity on galactic scales. Thus, this endeavour not only seeks to refine our measurement of h, but to advance our understanding of the Universe at a fundamental level.