Ettore Majorana (5.08.1906-25/26.03.1938) was an Italian theoretical physicist. He was born in Catania (Sicily). He studied at the technical school attached to the University of Rome. He furthered his knowledge in Leipzig and Copenhagen. In 1937 he was professor in Naples.
His work was in the field of atomic, molecular and nuclear physics. In 1932, drawing on the experiments of I. and F. Joliot-Curie, he supposed the existence of a new neutral particle, the neutron. He developed (1933) the theory of exchange forces (Majorana forces) and in the same year showed (1933) that nuclear forces saturate. He discovered the infinite-dimensional representations of the Lorentz group and found covariant equations for particles of arbitrary spin (1932). He considered the real representation of spinors (Majorana spinors). In 1937 he formulated the two-component theory.