Neutrino

In 1930-31 the physicist, Wolfgang Pauli postulated a new fundamental particle of the universe, subsequently (1935) named by the physicist, Enrico Fermi, the neutrino ("little neutral one" in Fermi's Italian), an electrically uncharged particle associated with the negatively electrically charged particle, the electron, but presumed to have no mass, Pauli having postulated such an electron-associated neutrino to reconcile, based on adherence to the law of conservation of energy and momentum, the discrepancy between the energy of an electron emitted by an atom's nucleus — too small — and the energy change of the nucleus, the missing energy carried off by the postulated chargeless particle.