Quantum mechanics is a branch of physics; it was developed between 1900 and 1930, and it explains the behavior of sub-atomic particles, atoms, molecules and nuclei. Attempts to combine it with the general and special theory of relativity leads to new and revolutionary types of theories. Experimental evidence forced the creation of new concepts, like the particle properties of radiation, the wave properties of matter, the quantization of physical properties, or the idea that one can no longer know exactly where a single particle such as an electron is at any one moment.
Some of the basic insights of quantum mechanics.
- The elementary particles behave both like particles and like waves. (Particle/wave dualism)
- Energy is not continuous, but quantized: it comes in small but discrete units.
- Particle movement is inherently random, and can only be described by a probability wave function.
- Uncertainty principle: It is physically impossible to know the location and the momentum of a particle at the same time.
- The quantum world is extremely different from the world we live in.
- See also the following articles:
Short timeline of the discoveries.
- 1901 Planck Blackbody radiation
- 1905 Einstein Photoelectric effect
- 1913 Bohr Spectra theory
- 1922 Compton Photon scattering
- 1924 Pauli Exclusion principle
- 1925 de Broglie Matter waves
- 1926 Schroedinger Wave equation
- 1927 Heisenberg Uncertainty principle
- 1927 Davison & Wave properties of Germer electrons
- 1927 Born Interpretation of the wavefunction