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Democritus
Democritus was an influential Ancient Greek pre-Socratic philosopher primarily remembered today for his formulation of an atomic theory of the universe.[3]
The theory of Democritus held that everything is composed of "atoms", which are physically, but not geometrically, indivisible; that between atoms, there lies empty space; that atoms are indestructible; have always been, and always will be, in motion; that there are an infinite number of atoms, and kinds of atoms, which differ in shape -
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Aristotle
Aristotle was a Greek philosopher and scientist born in the city of Stagira, Chalkidice, on the northern periphery of Classical Greece. His father, Nicomachus, died when Aristotle was a child, whereafter Proxenus of Atarneus became his guardian. -
John Dalton
John Dalton FRS was an English chemist, physicist, and meteorologist. He is best known for his pioneering work in the development of modern atomic theory; and his research into colour blindness, sometimes referred to as Daltonism, in his honour. He clarified what he had pointed out in Meteorological Observations—that the air is not a vast chemical solvent as Antoine-Laurent Lavoisier and his followers had thought, but a mechanical system, where the pressure exerted by each gas in a mixture is in -
J.J. Thompson
Sir Joseph John "J. J." Thomson OM PRS was an English physicist. In 1897, Thomson showed that cathode rays were composed of previously unknown negatively charged particles, which he calculated must have bodies much smaller than atoms and a very large value for their charge-to-mass ratio. -
Robert Millikan
Robert A. Millikan was an American experimental physicist honored with the Nobel Prize for Physics in 1923 for his measurement of the elementary electronic charge and for his work on the photoelectric effect. In 1914 Millikan took up with similar skill the experimental verification of the equation introduced by Albert Einstein in 1905 to describe the photoelectric effect. He used this same research to obtain an accurate value of Planck’s constant. In 1921 Millikan left the University of Chicago -
Earnest Rutherford
Ernest Rutherford, 1st Baron Rutherford of Nelson, OM FRS was a New Zealand-born British physicist who became known as the father of nuclear physics. Encyclopædia Britannica considers him to be the greatest experimentalist since Michael Faraday. -
Neils Bohr
Niels Henrik David Bohr was a Danish physicist who made foundational contributions to understanding atomic structure and quantum theory, for which he received the Nobel Prize in Physics in 1922. Bohr developed the Bohr model of the atom, in which he proposed that energy levels of electrons are discrete and that the electrons revolve in stable orbits around the atomic nucleus but can jump from one energy level (or orbit) to another. Although the Bohr model has been supplanted by other models, its -
James Chadwick
Sir James Chadwick, CH, FRS was an English physicist who was awarded the 1935 Nobel Prize in Physics for his discovery of the neutron in 1932. During the Second World War, Chadwick carried out research as part of the Tube Alloys project to build an atomic bomb, while his Liverpool lab and environs were harassed by Luftwaffe bombing. When the Quebec Agreement merged his project with the American Manhattan Project, he became part of the British Mission, and worked at the Los Alamos Laboratory and
