  Astrophysical techniques have pioneered the discovery of neutrino mass
properties. Current cosmological observations give an upper bound on neutrino
masses by attempting to disentangle the small neutrino contribution from the
sum of all matter using precise theoretical models. We discover the
differential neutrino condensation effect in our TianNu N-body simulation.
Neutrino masses can be inferred using this effect by comparing galaxy
properties in regions of the universe with different neutrino relative
abundance (i.e. the local neutrino to cold dark matter density ratio). In
"neutrino-rich"' regions, more neutrinos can be captured by massive halos
compared to "neutrino-poor" regions. This effect differentially skews the halo
mass function and opens up the path to independent neutrino mass measurements
in current or future galaxy surveys.
