Physicists and astronomers

D

Dalton, John 1766-1844
Revived the theory proposed by Democritus that all matter was composed of small, indivisible particles that he called atoms. Proposed the law of partial pressures

Daniell, John Frederick 1790-1845
British physicist, meteorologist and chemist. Inventor of the Daniell cell and the hygrometer.

Darwin, Charles 1809-1882
Origin of the Species. Evolution.

Davisson, Clinton Joseph 1881-1958
First experimental observation of the wave nature of electrons. Nobel prize for this in 1937.

Davy, Sir Humphrey 1778-1829
Miners' lamp. Application of conduction of heat.

De Broglie, Louis Victor 1892-1987
French physicist. Proposed an equation for the wavelength of a particle. Discovered the wave nature of electrons in 1923 and was awarded the Nobel Prize for Physics for this work in 1929.

De Sitter, Willem 1872-1934
Born in the Netherlands he was director of the Leiden Observatory from 1919. Theory of the Universe. He proposed four dimensional space-time and its links with relativity.

Debye, Peter Joseph Wilhelm 1884-1966
Dutch physical chemist. Electrolytes and dipole moments. Debye theory of specific heat.

Democritus 460-370 BC
Greek philosopher and scientist. The founder of the atomic theory. Proposed the idea that matter was composed of tiny indivisible atoms.

Dewar, James 1842-1923
British physicist and chemist. Invented the Dewar vacuum flask.

Dirac, Paul Adrien Maurice 1902-1984
Born in Bristol, England. Awarded the Nobel Prize for Physics in 1933 for his work on wave mechanics (1925) and relativistic quantum mechanics (1927). Quantum electrodynamics. Predicted the existence of antiparticles.

Doppler, Christian Johann 1803-1853
An Austrian physicist who discovered the Doppler effect – the change of frequency and wavelength for a moving source or observer.