Quantum mechanics is the physical theory that describes how matter and light behave at the scale of atoms and subatomic particles. It began in 1900, when Max Planck proposed that energy is emitted in discrete packets, or quanta, in order to explain the radiation from hot objects. Albert Einstein used the idea to explain the photoelectric effect in 1905, and Niels Bohr applied it to the structure of the atom in 1913. In the mid-1920s Werner Heisenberg, Erwin Schrodinger and others built a full mathematical theory, in which particles are described by probabilities and can show wave-like behaviour. Quantum mechanics is the basis of chemistry, semiconductors, lasers and medical imaging, and its interpretation is still debated.
Before and after
- c. 1900sRise of Expressionism
- 19th centuryConstruction of Maidan Nezalezhnosti
- 1900Founding of RCD Espanyol de Barcelona
- c. 1900sRise of modernism
- 1900Quantum mechanics
- 1900Sponge divers find the Antikythera wreck
- 1900The Library Cave of Dunhuang is discovered
- 1900Mendel's laws are rediscovered
- 19001900 becomes the warmest year on record
More in Science & technology
- 1789Discovery of uranium
- 1807Discovery of potassium
- 30 June 1808Discovery of boron
- 1810Discovery of fluorine
- 1823Discovery of silicon
- 1898Discovery of neon
The era
This moment belongs to the Industrial era (1760 CE to 1914 CE), steam, factories and revolutions. You can also browse everything in the 19th century.