 His main scientific results were on slow neutrons in the Fermi group, and the evidence for antiproton annihilations with emulsion techniques, somewhat contemporary to its production in accelerators by Emilio Segrè and collaborators.Amaldi co-authored about 200 scientific publications ranging from atomic spectroscopy and nuclear physics to elementary particle physics and experimental gravitation, as well as textbooks for secondary schools and universities.He also wrote historical-scientific books, like for example, the biography of his missing friend Ettore Majorana.