The facility will look for changes in neutrinos shot from both Fermilab (near Chicago) as well as exploding stars. Differences between neutrinos and antineutrinos could explain why the cosmos is dominated by matter, for instance. And looking to the stars could both help detect phenomenons (such as the births of black holes and neutron stars) and explain whether or not protons ever decay. Ultimately, it could help establish a unified scientific theory that explains... well, everything. However much time and money it takes to build LBNF, it could pay huge dividends down the road.