1920
ID: 392
Hilbert proposes his program to prove consistency of mathematics using finitary methods
ID: 392
1920
ID: 398
Thoralf Skolem extends Löwenheim's theorem to what becomes Löwenheim-Skolem theorem
ID: 398
1920
ID: 1284
George Bernard Shaw: 'You would not be allowed to be poor. You would be forcibly fed, clothed, lodged, taught, and employed'
ID: 1284
1920
ID: 1285
Henry Ford distributed 2 million free copies of The International Jew to libraries and schools
ID: 1285
1920
ID: 1286
American Prohibition begins; Haganah formed in Palestine
ID: 1286
1920
ID: 1287
Rev. Harry Ward 'Already a convinced Communist... cooperating and collaborating with the Communist Party'
ID: 1287
1920
ID: 1289
First commercial radio station (KDKA) begins broadcasting
ID: 1289
1920
ID: 1290
Standard costing systems developed for mass production industries like automobiles
ID: 1290
1920
ID: 1291
First commercial radio broadcasts using mathematical signal processing - Fourier analysis enables mass communication
ID: 1291
1920
ID: 1292
Stefan Banach develops systematic functional analysis - Creates theory of Banach spaces and linear operators
ID: 1292
1920
ID: 1293
Prohibition in United States inadvertently boosts chemical industry as companies pivot from alcohol to industrial chemicals
ID: 1293
1920
ID: 1294
New York diphtheria outbreak: 2,773 cases, 274 deaths
ID: 1294
1920
ID: 1295
250,000 US children die annually from poverty
ID: 1295
1920
ID: 1296
Diphtheria toxoid introduced, followed by mortality spike
ID: 1296
1920
ID: 1297
Amphetamines first synthesized in late 1920s; initially marketed as Benzedrine inhalers for nasal congestion
ID: 1297
1920
ID: 1298
American eugenics movement provides model for Nazi racial policies; Harry Laughlin's model sterilization law becomes basis for Nazi legislation
ID: 1298
1920
ID: 1299
Rockefeller Foundation funds Kaiser Wilhelm Institute eugenics research in Germany
ID: 1299
1920
ID: 4228
C-T-R introduces printing tabulator to compete with Powers machines - can print results directly on paper
ID: 4228
1920
ID: 4286
Color-coded filing systems become widespread - visual organization improves retrieval speed
ID: 4286
1920
ID: 4288
Over 500,000 women work as typists and stenographers in U.S. - typewriter enables women's entry into office work
ID: 4288
1920
ID: 5570
Admiral Miklós Horthy becomes Regent of Kingdom of Hungary - kingdom without a king ruled by admiral without navy
ID: 5570
1920
ID: 5599
VDI (Verein Deutscher Ingenieure) establishes machining research committees - systematic study of cutting forces and tool wear
ID: 5599
1920
ID: 5787
Prohibition destroys American cider tradition - FBI burns countless orchards, cider-making knowledge lost
ID: 5787
1920
ID: 5901
Heck brothers attempt to recreate aurochs - German zoologists breed cattle to resemble extinct aurochs, supported later by Nazis
ID: 5901
1920
ID: 1283
May 23, 1920
Pope Benedict XV issues 'Pacem Dei Munus Pulcherrimum' on peace and Christian reconciliation
ID: 1283
1920
ID: 5569
June 4, 1920
Treaty of Trianon - Hungary loses 72% of territory and 64% of population, 3.3 million Hungarians outside borders
ID: 5569
1920
ID: 1288
October 1920
Lenin tells Russian Young Communist League: 'We do not believe in God... Our morality is entirely subordinated to the interests of the proletariat's class struggle.'
ID: 1288