Magnetic moments

Felix Bloch calculated the magnetic moment of the neutron, a particle thought to have no magnetic field. This suggested it might be a particle made up of more fundamental particles that did have electrical charges. His work also implied the possible existence of an anti-neutron.
 Felix Bloch United States 1939 Magnetic moments

Felix Bloch calculated the magnetic moment of the neutron, a particle thought to have no magnetic field. This suggested it might be a particle made up of more fundamental particles that did have electrical charges. His work also implied the possible existence of an anti-neutron.