rights activist Heinrich Louis d'Arrest, Prussian astronomer, died in Copenhagen Ove Arup (1895–1988), Danish-born leading engineer, founder of Arup Caspar Bartholin the Elder (1585–1629) Caspar Bartholin the Younger (1655–1738) Rasmus Bartholin (1625–1698) Thomas Bartholin (1616–1680) Tove Birkelund (1928=1986), historical geologist Aage Bohr (1922–2009), physicist and Nobel Prize laureate Harald Bohr (1887–1951), mathematician Niels Bohr (1885–1962), physicist and Nobel Prize laureate Tycho Brahe (1546–1601), provided the observational data for Kepler's laws of planetary motion Johannes Nicolaus Brønsted (1879–1947) Karen Callisen (1882–1970), geologist Claudius Clavus (Claudius Claussøn Swart) (1388–?) Carl Peter Henrik Dam (1895–1976) Willi Dansgaard (1922–2011), geophysics Johan Ludvig Emil Dreyer (1852–1926), Danish-born astronomer A. K. Erlang, engineer, industrial and systems engineer Henning Frederik Feilberg (1831–1921), philologist, folklorist and writer Johannes Andreas Grib Fibiger, physician and Nobel Prize laureate Thomas Fincke (1561–1656), mathematician Niels Ryberg Finsen (1860–1904), physician and Nobel Prize laureate Bent Flyvbjerg, geographer and theorist of phronetic social science Anca Giurchescu (1930–2015), Romanian-born folk dance researcher and academic Hans Christian Gram (1853–1938), bacteriologist (gram staining) Jørgen Pedersen Gram Marie Hammer (1907–2002), zoologist Emil Christian Hansen (1842–1909), Saccharomyces carlsbergensis Peter Andreas Hansen (1795–1874) David Heinemeier Hansson, Ruby on Rails (lives in the US) Lene Hau (1959–), physicist and professor at Harvard University Piet Hein (1905–1996), poet and designer Anders Hejlsberg, Turbo Pascal, Delphi, C# (lives in the US) Ejnar Hertzsprung (1873–1967), astronomer Harald Hirschsprung (1830–1916), physician Niels Kaj Jerne, immunologist and Nobel Prize laureate Wilhelm Johannsen (1857–1927), coined the term "gene" Johannes Juul (1887–1969), inventor of wind turbines Jens Martin Knudsen (1930–2005) Evald Tang Kristensen (1843–1929), folklore collector Schack August Steenberg Krogh, physiologist and Nobel Prize laureate Niels A. Lassen, neuroimaging pioneer Inge Lehmann (1888–1993), seismologist (Earth's inner core) Rasmus Lerdorf, PHP (born in Greenland, lives in the US) Bergnart Carl Lewy (1817–1863), professor of chemistry Bodil Jerslev Lund (1919–2005), Danish chemist and pharmacist Peter Wilhelm Lund (1801–1880), paleontologist and zoologist, founder of Brazilian paleontology Conrad Malte-Brun (1775–1826) Georg Mohr (1640–1697), mathematician Peter Naur (1928–2016), Algol 60 and Backus-Naur form; Turing Award winner Ebbe Nielsen (1950–2001), entomologist Holger Bech Nielsen, physicist, co-inventor of string theory Jakob Nielsen (1890–1959), mathematician Jakob Nielsen (1957–), usability (lives in the US) Asger Skovgaard Ostenfeld (1866–1931), civil engineer Julius Petersen (1839–1910), mathematician Ragna Rask-Nielsen (1900–1998), biochemist Christen C. Raunkiær (1860–1938), ecologist and botanist, plant life-form Ole Rømer (1644–1710), first to calculate the speed of light Ozer Schild (1930–2006), Danish-born Israeli academic, President of the University