Timeline of Scientific Discoveries - 20th Century

20th Century

• 1905 – Albert Einstein: theory of special relativity, explanation of Brownian motion, and photoelectric effect
• 1906 – Walther Nernst: Third law of thermodynamics
• 1909 – Fritz Haber: Haber Process and also the Oil drop experiment by Robert Andrews Millikan to determine the charge on an electron
• 1911 – Ernest Rutherford: Atomic nucleus
• 1911 – Heike Kamerlingh Onnes: Superconductivity
• 1912 – Alfred Wegener: Continental drift
• 1912 – Max von Laue : x-ray diffraction
• 1913 – Henry Moseley: defined atomic number
• 1913 – Niels Bohr: Model of the atom
• 1915 – Albert Einstein: theory of general relativity – also David Hilbert
• 1915 – Karl Schwarzschild: discovery of the Schwarzschild radius leading to the identification of black holes
• 1918 – Emmy Noether: Noether's theorem – conditions under which the conservation laws are valid
• 1920 – Arthur Eddington: Stellar nucleosynthesis
• 1924 – Wolfgang Pauli: quantum Pauli exclusion principle
• 1924 – Edwin Hubble: the discovery that the Milky Way is just one of many galaxies
• 1925 – Erwin Schrödinger: Schrödinger equation (Quantum mechanics)
• 1927 – Werner Heisenberg: Uncertainty principle (Quantum mechanics)
• 1927 – Georges Lemaître: Theory of the Big Bang
• 1928 – Paul Dirac: Dirac equation (Quantum mechanics)
• 1929 – Edwin Hubble: Hubble's law of the expanding universe
• 1929 – Lars Onsager's reciprocal relations, a potential fourth law of thermodynamics
• 1934 – James Chadwick: Discovery of the neutron
• 1934 – Clive McCay: Calorie Restriction extends the maximum lifespan of another species Calorie_restriction#Research_history
• 1938 – Otto Hahn and Fritz Strassmann: Nuclear fission
• 1943 – Oswald Avery proves that DNA is the genetic material of the chromosome
• 1947 – William Shockley, John Bardeen and Walter Brattain invent the first transistor
• 1948 – Claude Elwood Shannon: 'A mathematical theory of communication' a seminal paper in Information theory.
• 1948 – Richard Feynman, Julian Schwinger, Sin-Itiro Tomonaga and Freeman Dyson: Quantum electrodynamics
• 1951 – George Otto Gey propagates first cancer cell line, HeLa
• 1952 – Jonas Salk: developed and tested first polio vaccine
• 1953 – Crick and Watson: helical structure of DNA, basis for molecular biology
• 1963 – Lawrence Morley, Fred Vine, and Drummond Matthews: Paleomagnetic stripes in ocean crust as evidence of plate tectonics (Vine-Matthews-Morley hypothesis).
• 1964 – Murray Gell-Mann and George Zweig: postulate quarks leading to the standard model
• 1964 – Arno Penzias and Robert Woodrow Wilson: detection of CMBR providing experimental evidence for the Big Bang
• 1965 – Leonard Hayflick: normal cells divide only a certain number of times: the Hayflick limit
• 1967 – Jocelyn Bell Burnell and Antony Hewish discover first pulsar
• 1984 – Kary Mullis invents the polymerase chain reaction, a key discovery in molecular biology.
• 1986 – Karl Müller and Johannes Bednorz: Discovery of High-temperature superconductivity
• 1994 - Andrew Wiles proves Fermats Last Theorem
• 1995 – Michel Mayor and Didier Queloz definitively observe the first extrasolar planet around a main sequence star
• 1995 - Eric Cornell, Carl Wieman and Wolfgang Ketterle attained the first Bose-Einstein Condensate with atomic gases, so called fifth state of matter at extremely low temperature.
• 1997 – Roslin Institute: Dolly the sheep was cloned.
• 1997 – CDF and DØ experiments at Fermilab: Top quark.
• 1998 – Gerson Goldhaber and Saul Perlmutter observed that the expansion of the universe is accelerating.