Physicists and astronomers
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
meteorologist and chemist. Inventor of the Daniell cell and the hygrometer. Darwin, Charles
Origin of the Species. Evolution.
Davisson, Clinton Joseph
First experimental observation of the wave nature of
electrons. Nobel prize for this in 1937. Davy, Sir
Miners' lamp. Application of conduction of heat.
De Broglie, Louis Victor
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,
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
chemist. Electrolytes and dipole moments. Debye theory of specific heat. Democritus
Greek philosopher and scientist. The founder of the atomic
theory. Proposed the idea that matter was composed of tiny indivisible atoms. Dewar, James
British physicist and chemist. Invented the Dewar vacuum
flask.Dirac, Paul Adrien Maurice
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
physicist who discovered the Doppler effect – the change of frequency and wavelength for a
moving source or observer.