The Flavor Composition of the High-Energy Cosmic Neutrinos: Today and Tomorrow

Abstract: Neutrinos of cosmic origin are unique messengers to investigate the Universe. The discovery of TeV-PeV neutrinos of astrophysical origin opened a new window to the cosmos. The flavor composition of these neutrinos has emerged as a versatile probe of both high-energy astrophysics and fundamental physics, as they carry information on the neutrino production mechanisms as well as propagation effects across cosmological distances. In this talk, I will discuss physics scenarios that the flavor composition can probe, what the current IceCube data reveal, and how future capabilities will be improved with next-generation neutrino telescopes.