  We propose a novel method to study the ultra-light scalars, where compact
rotating objects undergo the phenomenon of superradiance to create
gravitational waves and neutrino flux signals. The neutrino flux results from
the 'right' coupling between the ultra-light scalars and the neutrinos. We
study the intertwining of gravitational waves and neutrino flux signals
produced from a single source and elaborate if and when the signals can be
detected in existing and upcoming experiments in a direct manner. We also
discuss an indirect way to test it by means of cosmic neutrino background which
can be detected by upcoming PTOLEMY experiment.
