Portal:History of science/Selected anniversaries/November 20
- 1602 – Birth of Otto von Guericke, German physicist (d. 1686)
- 1704 – Death of Charles Plumier, French botanist (b. 1646)
- 1764 – Death of Christian Goldbach, Prussian mathematician (b. 1690)
- 1778 – Death of Francesco Cetti, Italian Jesuit scientist (b. 1726)
- 1841 – Birth of Victor D'Hondt, Belgian mathematician (d. 1901)
- 1856 – Death of Farkas Bolyai, Hungarian mathematician (b. 1775)
- 1877 – Thomas Edison announces his invention of the phonograph, a machine that can record and play sound
- 1886 – Birth of Karl von Frisch, Austrian zoologist, Nobel laureate (d. 1982)
- 1889 – Birth of Edwin Hubble, American astronomer (d. 1953)
- 1905 – Albert Einstein's paper, Does the Inertia of a Body Depend Upon Its Energy Content?, is published in the journal "Annalen der Physik". This paper reveals the relationship between energy and mass. This leads to the mass–energy equivalence formula E = mc²
- 1908 – Death of Georgy Voronoy, Russian mathematician (b. 1868)
- 1910 – Birth of Willem Jacob van Stockum, Dutch physicist (d. 1944)
- 1945 – Death of Francis William Aston, British chemist, Nobel laureate (b. 1877)
- 1953 – The British Natural History Museum announces that the "Piltdown Man" skull, initially believed to be one of the most important fossilized hominid skulls ever found, is a hoax
- 1963 – Birth of Timothy Gowers, British mathematician
- 1976 – Death of Trofim Lysenko, Russian biologist (b. 1898)
- 2006 – Death of Zoia Ceauşescu, Romanian mathematician (b. 1950)