  High-energy cosmic neutrinos carry unique information about the most
energetic non-thermal sources in the Universe. This white paper describes the
outstanding astrophysics questions that neutrino astronomy can address in the
coming decade. A companion white paper discusses how the observation of cosmic
neutrinos can address open questions in fundamental physics. Detailed
measurements of the diffuse neutrino flux, measurements of neutrinos from point
sources, and multi-messenger observations with neutrinos will enable the
discovery and characterization of the most energetic sources in the Universe.
