Riccardo Giacconi (1931-2018) was an Italian astrophysicist who was awarded with the Nobel prize in physics back in 2002 for his important contributions to astrophysics.
Since he was an astrophysicist, he must have heard about the multiverse hypothesis. Still, I have not found a single paper or article or interview from him where he indicates his opinion (neither positive nor negative thoughts) about the possibility of the existence of multiple universes.
Therefore, does anybody know what did Mr. Giacconi thought about the multiverse hypothesis? Did he like it? Or, on the contrary, he thought it was nonsense and not worthy of any discussion or study?