Using Neutrino Oscillations to Measure $H_0$

Abstract

The tension between late and early universe probes of today's expansion rate, the Hubble parameter $H_0$, remains a challenge for the standard model of cosmology $\Lambda$CDM. There are many theoretical proposals to remove the tension, with work still needed on that front. However, by looking at new probes of the $H_0$ parameter one can get new insights that might ease the tension. Here, we argue that neutrino oscillations could be such a probe. We expand on previous work and study the full three-flavor neutrino oscillations within the $\Lambda$CDM paradigm. We show how the oscillation probabilities evolve differently with redshift for different values of $H_0$ and neutrino mass hierarchies. We also point out how this affects neutrino fluxes which, from their measurements at neutrino telescopes, would determine which value of $H_0$ is probed by this technique, thus establishing the aforementioned aim.