Discoveries
1900	Planck discovers the quantum nature of energy
1905	Einstein publishes the special theory of relativity
1912	Leavitt discovers a correlation between Cepheids' period and luminosity
1913	Rutherford and Bohr describe atomic structure
1915	Einstein announces the general theory of relativity
1924	Hubble identifies a new galaxy
1927	Big bang theory is introduced
1927	Heisenberg the states uncertainty principle
1929	Hubble finds proof that the universe is expanding
1931	Lawrence invents the cyclotron
1932	Chadwick discovers the neutron
1942	Fermi creates controlled nuclear reaction
1945	The first atomic bomb is detonated
1965	Penzias and Wilson discover cosmic microwave radiation
1967	Bell and Hewish discover pulsars
1976	Cosmic string theory introduced