History of the Atom Timeline

By Robert Barbaro

Democritus

460BC-370BC


The atomists held that there are two fundamentally different kinds of realities composing the natural world, atoms and void. Atoms, from the Greek adjective atomos or atomon, indivisible, are infinite in number and various in size and shape, and perfectly solid, with no internal gaps. They move about in an infinite void.

John Dalton

1766-1844

J.J. Thomson

1856-1940

Ernest Rutherford

1871-1937

Neils Bohr

1885-1962

Erwin Schrödinger

1887-1961