  Do void statistics contain information beyond the tracer 2-point correlation
function? Yes! As we vary the sum of the neutrino masses, we find void
statistics contain information absent when using just tracer 2-point
statistics. Massive neutrinos uniquely affect cosmic voids. We explore their
impact on void clustering using both the DEMNUni and MassiveNuS simulations.
For voids, neutrino effects depend on the observed void tracers. As the
neutrino mass increases, the number of small voids traced by cold dark matter
particles increases and the number of large voids decreases. Surprisingly, when
massive, highly biased, halos are used as tracers, we find the opposite effect.
The scale at which voids cluster, as well as the void correlation, is similarly
sensitive to the sum of neutrino masses and the tracers. This scale dependent
trend is not due to simulation volume or halo density. The interplay of these
signatures in the void abundance and clustering leaves a distinct fingerprint
that could be detected with observations and potentially help break
degeneracies between different cosmological parameters. This paper paves the
way to exploit cosmic voids in future surveys to constrain the mass of
neutrinos.
