The origin of the first billion-solar-mass supermassive black holes (SMBHs) emerged within the first billion years after the Big Bang is an unsolved puzzle. I will present a multi-messenger project to tackle this question, which combines multi-scale cosmological simulations, multi-wavelength radiative transfer and multi-phase gravitational waves. I will present viable formation models of the first SMBHs, and demonstrate that a light-and-sound synergy between future electromagnetic telescopes, such as JWST, and gravitational waves detectors, such as LISA, is necessary to test models of black hole seed and growth path of the first SMBHs.
Raffaella Schneider e Gianluca Cavoto