Karl Reinhold Geijer

Russian mathematician | Clay Research Award (2017) | Saint Petersburg State University | Saint Petersburg: April 23, 1974 - Tbilisi: March 18, 2015 | Eugenia

Dutch philosopher | Eureka Prize for Science Communication (2002), Golden Owl (2002) | Utrecht University | De Bilt: April 23, 1968 - Manhattan: April 9, 1939

Russian mathematician | Moscow State University | Moscow: April 23, 1967 - Simferopol: May 18, 2020 | Nikolay Moshchevitin | Moscow: April 23, 1967

Spanish chemist | Toledo: April 23, 1964 - Zurich: November 15, 1981 | Rosa María Martín Aranda (Rosa Maria Martin Aranda) | Toledo: April 23, 1964 - Zurich

April 23, 1963 - Tarusovo: December 13, 1853 | Zuzana Kovačičová (Zuzana Kovacicova) | April 23, 1963 - Tarusovo: December 13, 1853

Israeli epidemiologist and public health researcher | Hebrew University of Jerusalem (1994), Technion – Israel Institute of Technology (1989) | Tel Aviv

American philosopher of science (born 1958) | Guggenheim Fellowship (2008) | University of Pittsburgh, Yale University | Washington, D.C.: April 23, 1958

American mathematician | Hausdorff medal (2013), Tarski Lectures (2018), Gödel Lecturer (2008), Carol Karp Prize (1988), Fellow of the American Academy of

British scientist | Fellow of the Optical Society, Faraday Medal and Prize (2022), Royal Society Wolfson Fellowship, Young Medal and Prize (2015) | MSU Faculty

American academic | University of California, Los Angeles | Los Angeles: April 23, 1954 - Stockholm: February 8, 2005 | Andrew B. Bocarsly | Los Angeles: April

Silver Cross of Merit | Warsaw University of Technology | April 23, 1954 - 14th arrondissement of Paris: December 30, 1993 | Wojciech Nasierowski | April

Czech philosopher, professor, publicist, translator and university educator | Charles University | Písek: April 23, 1953 - Toronto: August 3, 2017 | Pavel

Algerian writer and anthropologist (1953–2016) | Dictionnaire Amoureux de l'Algérie | Sciences Po, Paris Diderot University, Constantine 1 University

Scottish bagpiper and pharmacist | Glasgow: April 23, 1950 - Scotland: May 6, 2020 | Iain MacDonald | Glasgow: April 23, 1950 - Scotland: May 6, 2020

French philosopher and Islamologist | Grand prix de philosophie (2017), Officer of Arts and Letters (2014), prix Gegner (2013), Concours général (1966)

American fiction writer, essayist, and academic | Guggenheim Fellowship (1987), National Book Award for Fiction (1990), MacArthur Fellows Program (1998)

Belgian mathematician (1947-) | Hasselt University | Menen: April 23, 1947 - San Francisco: September 7, 1940 | Freddy Dumortier | Menen: April 23, 1947 - San

Soviet and Russian physicist (1944–2018) | USSR State Prize (1983), Max Born Award (1997), Fellow of the Optical Society | MSU Faculty of Physics, Institute

Polish logician (1943–2009) | Gold Cross of Merit, Knight of the Order of Polonia Restituta | Jagiellonian University | Aix-les-Bains: April 23, 1943

English musician, 1943-2005 | Worcester College, Westminster School | Exmouth: April 23, 1943 - London: January 1, 2005 | Hugh Seymour Davies | Exmouth: April

American logician (1942–2016) | University of California, Berkeley | Missoula: April 23, 1942 - December 22, 2016 | Jack Silver | Missoula: April 23, 1942

French philosopher | Hannah Arendt Prize (2017) | Reading Capital (work level) | École Normale Supérieure | Avallon: April 23, 1942 - London: January 1, 1974

German nuclear chemist and astrophysicist | Glenn T. Seaborg Award for Nuclear Chemistry (1999), Hans A. Bethe Prize (2014) | Jena: April 23, 1941 - March 23, 2025

American computer programmer (1941-2016) | Internet Hall of Fame (2012), Eduard-Rhein Cultural Award (2011), Princess of Asturias Award for Technical and

Bishop of Płock, Archbishop of Warsaw, Polish Communist Secret Police informer | Idzi Radziszewski prize (2007), Pro Memoria Medal, Officer of the Order of

Russian physicist | State Prize of the Russian Federation | Odesa University | Wołosate: April 23, 1936 - Novosibirsk: April 7, 2015 | Svyatoslav Gabuda

American ethnomathematician | New York City: April 23, 1935 - June 11, 2013 | Marcia Ascher | New York City: April 23, 1935 - June 11, 2013

American mathematician and rocket scientist | Cleveland State University, Xavier University of Louisiana | Birmingham: April 23, 1932 - Cleveland: June 25, 2011

Soviet scientist | Merited Scientist of the Russian Federation | Peter the Great Saint Petersburg State Polytechnical University | Saint Petersburg: April 23

New Zealand cartoonist, columnist, scientist and ecologist (1932–2025) | Member of the New Zealand Order of Merit (2013), Cranwell Medal (1999), Foundation

Romanian chemist | Bolyai University | Cluj-Napoca: April 23, 1931 - Brighton: September 22, 1956 | Ernő Grünwald (Erno Grunwald) | Cluj-Napoca: April 23

German chemist | Dürrhennersdorf: April 23, 1931 - Leipzig: April 18, 2011 | Siegfried Hauptmann | Dürrhennersdorf: April 23, 1931 - Leipzig: April 18, 2011

American writer (1928–2020) | honorary doctorate from ENS (2014), honorary doctor of the Catholic University of Louvain (1980), Guggenheim Fellowship (1971)

Russian physician | Order of the Patriotic War 2nd class, USSR State Prize, Order of the Badge of Honour, Order of Lenin, Honoured worker in science and

American logician and computational neuroscientist (1923-1969) | Guggenheim Fellowship | Detroit: April 23, 1923 - Cambridge: May 14, 1969 | Walter Pitts

Hungarian philosopher | Budapest University of Jewish Studies, Eötvös Loránd University | Győr: April 23, 1920 - London Borough of Hillingdon: January 24, 1999

Dutch curator and physicist (1917–2010) | honorary doctor of the Maria Curie-Skłodowska University, Honorary doctor of the University of Liège | Leiden University

SRI International executive (1917–2001) | Commander of the Order of the British Empire, Legionnaire of Legion of Merit | Stanford Graduate School of

Stalin Prize, 3rd degree, Order of the Patriotic War 2nd class | Moscow Power Engineering Institute | April 23, 1912 - New York: July 5, 1979 | Leonid

Russian mathematician | Herzen University, Faculty of Physics and Mathematics of the Saint Petersburg University | Cholmieč: April 23, 1908 - Saint

Soviet paleontologist, science fiction author and social thinker (1908–1972) | Stalin Prize, 2nd degree (1952), Order of the Red Banner of Labour (1967)

mathematician (1907-1984) | Technische Hochschule Berlin, Technische Universität Berlin | Turda: April 23, 1907 - Budapest: August 14, 1984 | Samu Borbély

Czech philosopher, pychiatrist, psychologist and writer | Masaryk University Faculty of Arts | Brno: April 23, 1906 - Brno: October 15, 1981 | Robert Konečný

American mathematician (1902-1988) | Washington & Jefferson College, Johns Hopkins University | McKeesport: April 23, 1902 - Clinton: July 12, 1988 | Boyd

Icelandic author (1902-1998) | Nobel Prize in Literature (1955) | Reykjavík: April 23, 1902 - Mosfellsbær: February 8, 1998 | Halldór Laxness - Halldór

Russian metallurgist (1901-1953) | Honoured Worker of Science and Technology of the RSFSR, Stalin Prize, Medal "In Commemoration of the 800th Anniversary of

American chemist | Vassar College | New Haven: April 23, 1900 - Lviv: January 4, 2021 | Mildred Virginia Cox | New Haven: April 23, 1900 - Lviv: January 4, 2021

Russian astronomer | Order of the Badge of Honour, Medal "For Valiant Labour in the Great Patriotic War 1941–1945", Order of Lenin, Stalin Prize, VDNKh gold medal

April 23, 1893 - San Diego: April 24, 1987 | Lili Wachenheim | April 23, 1893 - San Diego: April 24, 1987

Indian Bengali chemist (1893-1983) | Commander of the Order of the British Empire, Fellow of the Royal Society of Chemistry, Padma Bhushan in science & engineering

American mathematician | Harvard University, University of Chicago | Troy Grove: April 23, 1879 - Atlanta: September 10, 1947 | William Vernon Skiles | Troy

German philosopher (1876–1956) | University of Jena | Stadtlauringen: April 23, 1876 - Zurich: January 12, 1956 | Fritz Medicus | Stadtlauringen: April 23

Order of the Red Banner of Labour, Honored Scientist of the RSFSR | S. M. Kirov Military Medical Academy, Imperial Academy of Medical Surgery | April 23

German mathematician (1869-1928) | Friedrich-Wilhelms-Gymnasium, Martin Luther University Halle-Wittenberg, Humboldt University of Berlin | Berlin: April 23

Danish physician | commander of the Order of the Dannebrog (1926), doctor honoris causa from the University of Paris (1927), Nobel Prize in Physiology or Medicine (1926)

Czech biologist (1866-1936) | Zbýšov: April 23, 1866 - Běloves: June 7, 1936 | Ivan Honl | Zbýšov: April 23, 1866 - Běloves: June 7, 1936

Soviet geologist | Saint Petersburg Mining Institute | Barnaul: April 23, 1864 - Saint Petersburg: August 7, 1932 | Nikolay Vysotsky | Barnaul: April 23, 1864

German chemist (1861–1933) | Adolf-von-Baeyer Gold Medal (1924) | Kamen: April 23, 1861 - Leverkusen: May 10, 1933 | Bernhard Heymann | Kamen: April 23, 1861

British Army general (1861-1936) | Knight Grand Cross of the Order of St Michael and St George, King George V Silver Jubilee Medal, Knight Grand Cross of the

German theoretical physicist (1858–1947) | Max Planck Medal (1929), honorary doctor of the University of Athens, Bavarian Maximilian Order for Science and

American inventor | National Inventors Hall of Fame (2006) | Columbus: April 23, 1856 - New York City: January 30, 1910 | Granville Tailer Woods. Black Edison

Austrian meteorologist (1856-1920) | Humboldt University of Berlin, University of Vienna | Brody: April 23, 1856 - Perchtoldsdorf: October 4, 1920 | Max

Austrian mathematician, physicist, explorer and botanist (1852-1915) | Grave of honor | Schottengymnasium, University of Vienna, University of Regensburg

German mathematician, natural scientist and teacher | University of Greifswald, University of Göttingen, Gymnasium Theodorianum, Frederick William University

Hungarian poet, philosopher, translator (1840-1898) | Aiud: April 23, 1840 - Cluj-Napoca: July 7, 1898 | Béla Szász (Bela Szasz) | Aiud: April 23, 1840

American inventor | Elliott Cresson Medal (1890) | University of Vermont | South Boston: April 23, 1839 - St. Augustine: January 27, 1913 | James B. Hammond

April 23, 1837 - Turin: November 1, 1895 | Louis Durand | April 23, 1837 - Turin: November 1, 1895

Dutch philosopher, historian and musicologist (1834-1897) | Delft: April 23, 1834 - Arnhem: April 30, 1897 | Jan Pieter Nicolaas Land | Delft: April 23, 1834

German chemist (1833-1889) | University of Göttingen | Neustadt bei Coburg: April 23, 1833 - Jena: August 23, 1889 | Johann Georg Anton Geuther | Neustadt bei

Czech mathematician and educator (1828–1863) | Opočno: April 23, 1828 - Prague: October 9, 1863 | Rudolf Skuherský (Rudolf Skuhersky) | Opočno: April 23

American dentist | New London: April 23, 1827 - New London: November 4, 1897 | Washington Sheffield | New London: April 23, 1827 - New London: November 4, 1897

Spanish politician (1821-1885) | Seville: April 23, 1823 - Madrid: July 2, 1885 | Roque Barcia Martí (Roque Barcia Marti) | Seville: April 23, 1823 - Madrid

French writer | Bourges: April 23, 1816 - Paris: November 3, 1887 | Charles Marie Zévort (Charles Marie Zevort) | Bourges: April 23, 1816 - Paris: November 3, 1887

Polish writer and inventor | Silver Cross of the Virtuti Militari (1831) | April 23, 1805 - Derry: February 24, 1899 | George Renczynski | April 23, 1805

German philosopher (1805–1879) | Martin Luther University Halle-Wittenberg, Heidelberg University, Humboldt University of Berlin | Magdeburg: April 23, 1805

Qing dynasty Chinese scholar (1794-1857) | Illustrated Treatise on the Maritime Kingdoms | Shaoyang: April 23, 1794 - Hangzhou: January 1, 1856 | Wei Yuan

British astronomer (1792–1882) | Fellow of the Royal Society, Fellow of the Royal Society of Edinburgh, Pour le Mérite for Sciences and Arts order, Royal Medal (1862)

German church leader | University of Göttingen | Hildesheim: April 23, 1780 - Berlin: May 31, 1846 | Philip Marheineke | Hildesheim: April 23, 1780 - Berlin

theologian and historian from Hungary | Keszthely: April 23, 1766 - Pest: July 2, 1851 | George Fejer | Keszthely: April 23, 1766 - Pest: July 2, 1851

University of Tübingen | April 23, 1763 - India: December 10, 2009 | Karl Friedrich Hipp | April 23, 1763 - India: December 10, 2009

German astronomer | Fellow of the Royal Society | University of Jena | Wasungen: April 23, 1679 - Giessen: September 17, 1749 | Johann Georg Liebknecht

French geologist and archaeologist | Nîmes: April 23, 1678 - Neuchâtel: December 31, 1742 | Louis Bourguet | Nîmes: April 23, 1678 - Neuchâtel: December 31, 1742

Dutch mathematician (1628-1704) | Academy of Saumur, Leiden University | Amsterdam: April 23, 1628 - Amsterdam: April 15, 1704 | Johannes Hudde - Johannes van

Italian philosopher and scientist | Florence: April 23, 1604 - Florence: February 6, 1673 | Orazio Ricasoli Rucellai | Florence: April 23, 1604 - Florence