Dalton came up with the atomic theory which states that all matter was composed of small indivisible atoms, atoms of a given element possess unique characteristics and weight, and there are three different types of atoms.

Goldstein is known as the discoverer of protons. He also did experiments with cathode ray tubes.

Thomson discovered the electron in 1897. He also concluded that electrons had a mass that was 1000 times smaller than a hydrogen atom.

In 1898 Rutherford discovered alpha and beta rays in uranium radiation. in 1910 he came up with the concept of the nucleus.

Planck is the originator of the quantum theory, which helps with understanding the atomic and subatomic processes.

Millikan was an american physicist who determined the charge on an electrons using charged oil drop experiments.

Moseley determined the number of positive charges in the nucleus by measuring the wavelength of the x-rays given off by certain metals.

Bohr came up with the theory that electrons only travel in certain successively larger orbits. He also determined that the outer rings hold more electrons than the inner rings. He also determined that when an electron jumps from an outer orbit to an inner one, they emit light.

Einstein came up the the general theory of of relativity and the photon theory of light and the theory of gravitation He also contributed to the theory of radiation and statistical mechanics.

De Broglie introduced the theory of particle-wave duality.

Schrodinger invented wave mechanics, which are used in quantum physics.

Heisenberg came up with the uncertainty principles and developed the operator methods for the solution of quantum mechanical problems.

James Chadwick proved the existence of neutrons and contributed to the successful controlled fissioning of Uranium-235. He also eventually contributed to the development of the atomic bomb.