Science
- Planck's law of black body radiation
- Einstein's theory of special relativity
- Einstein explains Brownian motion and the photoelectric effect
- Seismographs built in the University of California, Berkeley, in 1900
- Practical air conditioner designed by Willis Carrier in 1902
- Geiger Counter (measures radioactivity) invented by Hans Geiger in 1908
- Radioactivity discovered by Marie Curie
- Third Law of Thermodynamics by Walther Nernst
- Quantum Hypothesis by Max Planck in 1900
- The Bacillus Calmette-Guérin (BCG) immunization for tuberculosis is first developed.
Read more about this topic: 1900s (decade)