People Behind the Development of Particle Model

Contribution of Democritus

400 BCE

Democritus greatest contribution to modern science was arguably related to the atomic theory. According to Democritus' atomic theory, the universe and all matter obey the following principles: Everything is composed of “atoms”, which are physically, but not geometrically, indivisible. Thus he was the first person who was able to propose the existence of atoms, way back in 400 BCE during the time period of the Greeks. Many years later it was confirmed that the idea of Democritus was correct.

Contribution of Isaac Newton

1672

Isaac Newton also had a great role in the development of the particle model. He argued that the geometric nature of reflection and refraction of light could only be explained if light were made of particles, referred to as corpuscles, because waves do not tend to travel in straight lines. Newton disproved Huygens' theory that light was made of waves. Despite the highly regarded reputation of Sir Isaac Newton, a number of prominent scientists in the early 1700s did not agree with his theory.

Contribution of John Dalton

1803

Dalton is best known for Dalton's law. These are its postulate:
All matter is made up of very tiny particles called atoms
Atoms are indivisible particles which cannot be created or destroyed in a chemical reaction
Atoms of a given element are identical in mass and chemical properties
Atoms of different elements have different masses and chemical properties
Atoms combine in a ratio of small whole numbers to form compounds
The relative number and kinds of atoms are constant in a given compound

Contribution of Albert Einstein

1905

Albert Einstein had an tremendous role in the development of the particle model.
Einstein created a quantum theory of light, the idea that light exists as tiny packets, or particles, which he called photons.