Majorana was very young when he joined Enrico Fermi's work group in Rome (becoming one of the famous so-called "via Panisperna's boys" - from the address of their laboratory) and specialized in atomic spectroscopy. He worked on a theory about the energies that can give steadyness to the atom, which later would have been known as Heisenberg's theory.
He disappeared in unclear circumstances during a boat trip from Naples to Palermo. Many investigations were made to understand what had happened, but Majorana equally could have suicided (he left two letters which contained a sort of farewell), could have been kidnapped or could have voluntarily intended to disappear, and in this latter case political reflections do apply, since he was working in the fascist Italy for the studies which would have brought to the invention of the atomic bomb.
The most important results of those investigations are widely described in Leonardo Sciascia's book "Il caso Majorana".
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