---
title: "List of multiple discoveries"
chunk: 4/7
source: "https://en.wikipedia.org/wiki/List_of_multiple_discoveries"
category: "reference"
tags: "science, encyclopedia"
date_saved: "2026-05-05T03:44:22.470419+00:00"
instance: "kb-cron"
---

E = mc2, though only Einstein provided the accepted interpretation – Henri Poincaré, 1900; Olinto De Pretto, 1903; Albert Einstein, 1905; Paul Langevin, 1906. 1902: Walter Sutton and Theodor Boveri independently proposed that the hereditary information is carried in the chromosomes. 1902: Richard Assmann and Léon Teisserenc de Bort independently discovered the stratosphere. 1904: Epinephrine synthesized independently by Friedrich Stolz and by Henry Drysdale Dakin. 1905: Brownian motion was independently explained by Albert Einstein (in one of his 1905 papers) and by Marian Smoluchowski in 1906. 1905: The Einstein Relation was revealed independently by William Sutherland in 1905, by Albert Einstein in 1905, and by Marian Smoluchowski in 1906. 1905: The chromosomal XY sex-determination system—that males have XY, and females XX, sex chromosomes—was discovered independently by Nettie Stevens, at Bryn Mawr College, and by Edmund Beecher Wilson at Columbia University. 1907: Lutetium discovered independently by French scientist Georges Urbain and by Austrian mineralogist Baron Carl Auer von Welsbach. 1907: Hilbert space representation theorem, also known as Riesz representation theorem, the mathematical justification of the Bra-ket notation in the theory of quantum mechanics –  independently proved by Frigyes Riesz and Maurice René Fréchet. 1908: The Hardy–Weinberg principle is a principle of population genetics that states that, in the absence of other evolutionary influences, allele and genotype frequencies in a population will remain constant from generation to generation. This law was formulated in 1908 independently by German obstetrician-gynecologist Wilhelm Weinberg and, a little later and a little less rigorously, by British mathematician G.H. Hardy. 1908: The Stark–Einstein law (aka photochemical equivalence law, or photoequivalence law) – independently formulated between 1908 and 1913 by Johannes Stark and Albert Einstein. It states that every photon that is absorbed will cause a (primary) chemical or physical reaction. 1908: Frequency-hopping spread spectrum in radio work was described by Johannes Zenneck (1908), Leonard Danilewicz (1929), Willem Broertjes (1929), and Hedy Lamarr and George Antheil (1942 US patent). 1911: Ejnar Hertzsprung created the Hertzsprung–Russell diagram, abbreviated H–R diagram, HR diagram, or HRD – a scatter plot of stars showing the relationship between the stars' absolute magnitudes or luminosities versus their stellar classifications or effective temperatures – a major step toward an understanding of stellar evolution. In 1913 the Hertzsprung–Russell diagram was independently created by Henry Norris Russell. 1912-1917: Alexander Bogdanov formulated principles such as feedback, dynamic equilibrium, synergy, and the theory of constraints under the transdisciplinary framework of "tektology". A number of very similar approaches were founded by Ludwig von Bertalanffy (general systems theory, 1950s), Hermann Schmidt (allgemeine Regelkreislehre (universal science of feedback, 1930s), Ștefan Odobleja (psychologie consonantiste, 1936) and Norbert Wiener (cybernetics, 1945). By 1913, vitamin A was independently discovered by Elmer McCollum and Marguerite Davis at the University of Wisconsin–Madison, and by Lafayette Mendel and Thomas Burr Osborne at Yale University, who studied the role of fats in the diet. 1915: Bacteriophages (viruses that infect bacteria) – Frederick Twort (1915), Félix d'Hérelle (1917). 1915: Rotor cipher machines – Theo A. van Hengel and R.P.C. Spengler (1915); Edward Hebern (1917); Arthur Scherbius (Enigma machine, 1918); Hugo Koch (1919); Arvid Damm (1919). 1917–1921: Crystal oscillator – Alexander M. Nicolson (1917, using Rochelle salt); Walter Guyton Cady (1921, using quartz). 1921: The simultaneous discovery of Ramsauer-Townsend effect by Carl Ramsauer and John Sealy Townsend (1921). 1922: Sound film – Joseph Tykociński-Tykociner (1922), Lee De Forest (1923). 1922: The Big Bang theory of the universe—that the universe is expanding from a single original point—was developed from the independent derivation of the Friedmann equations from Albert Einstein's equations of general relativity by the Russian, Alexander Friedmann, in 1922, and by the Belgian, Georges Lemaître, in 1927. The Big Bang theory was confirmed in 1929 by the American astronomer Edwin Hubble's analysis of galactic redshifts. But the Big Bang theory had been presaged three-quarters of a century earlier in the American poet and short-story writer Edgar Allan Poe's then much-derided essay, Eureka: A Prose Poem (1848). 1923: Georgios Papanikolaou is credited with discovering as early as 1923 that cervical cancer cells can be detected microscopically, though his invention of the Pap test went largely ignored by physicians until 1943. Aurel Babeş of Romania independently made similar discoveries in 1927. 1923: Anodization: Benough-Stuart process developed in the United Kingdom by Guy Dunstan Bengough and John McArthur Stuart for duralumin seaplane corrosion protection using chromic acid (1923); independently, oxalic acid anodizing was developed in Japan by Tsunetaro Kujirai and Sakae Ueki at RIKEN (1924). 1924: "Primordial soup" theory of the abiogenetic evolution of life from carbon-based molecules – Alexander Oparin (1924), J.B.S. Haldane (1925). 1926: Jet stream was detected in the 1920s by Japanese meteorologist Wasaburo Oishi, whose work largely went unnoticed outside Japan because he published his findings in Esperanto. Often given some credit for discovery of jet streams is American pilot Wiley Post, who in the year before his 1935 death noticed that at times his ground speed greatly exceeded his air speed. Real understanding of the nature of jet streams is often credited to experience in World War II military flights. 1926: Borůvka's algorithm, an algorithm for finding a minimum spanning tree in a graph, was first published in 1926 by Otakar Borůvka. The algorithm was rediscovered by Choquet in 1938; again by Florek, Łukasiewicz, Perkal, Steinhaus, and Zubrzycki; and again by Sollin in 1965. 1927: The discovery of phosphocreatine was reported by Grace Palmer Eggleton and Philip Eggleton of the University of Cambridge and separately by Cyrus H. Fiske and Yellapragada Subbarow of Harvard Medical School. 1929: Dmitri Skobeltsyn first observed the positron in 1929. Chung-Yao Chao also observed the positron in 1929, though he did not recognize it as such. 1930s: Quantum electrodynamics and renormalization (1930s–40s): Ernst Stueckelberg, Julian Schwinger, Richard Feynman, and Sin-Itiro Tomonaga, for which the latter 3 received the 1965 Nobel Prize in Physics. 1930: Undefinability theorem, an important limitative result in mathematical logic – Kurt Gödel (1930; described in a 1931 private letter, but not published); Alfred Tarski (1933). 1930: Chandrasekhar Limit—published by Subramanyan Chandrasekhar (1931–35); also computed by Lev Landau (1932). Also Edmund Clifton Stoner and Wilhelm Anderson (1930)
1931: A theory of protein denaturation is widely attributed to Alfred Mirsky and Linus Pauling, who published their paper in 1936, though it had been independently discovered in 1931 by Hsien Wu, whom some now recognize as the originator of the theory. Electroluminescence in silicon carbide, now known as the LED, was discovered independently by Oleg Losev in 1927 and by H.J. Round in 1907, and possibly in 1936 in zinc sulfide by Georges Destriau, who believed it was actually a form of incandescence. 1932: Zipf's law, described by George Zipf (1932), was previously discovered by Felix Auerbach (1913), Jean-Baptiste Estoup (1916), Godfrey Dewey (1923), Edward U. Condon (1928). The law's naming after a later rediscoverer is therefore an example of Stigler's law of eponymy (named by Stephen Stigler after himself in 1980: see below). 1934: Natural deduction, an approach to proof theory in philosophical logic – discovered independently by Gerhard Gentzen and Stanisław Jaśkowski in 1934. 1934: The Gelfond–Schneider theorem, in mathematics, establishes the transcendence of a large class of numbers.