1564 - 1642

Galileo Galilei is considered by many to be the father of modern physics because of his willingness to replace old assumptions in favor of new scientifically deduced theories. He is famous for his celestial theories, and his works on mechanics paved the way for Newton.

1546 - 1601, 1571 - 1630

Tycho Brahe and Johannes Kepler. Brahe's accurate celestial data allow Kepler to develop his theory of elliptical planetary motion and provide evidence for the Copernican system. In addition, Kepler writes a qualitative description of gravitation.

1642 - 1727

Sir Isaac Newton develops the laws of mechanics (now called classical mechanics) which explains object motion in a mathematical fashion.

1773 - 1829

Thomas Young develops the wave theory of light and describes light interference.

1791 - 1867

Michael Faraday creates the electric motor, and develops an understanding of electromagnetic induction, which provides evidence that electricity and magnetism are related. In addition, he discovers electrolysis and describes the conservation of energy law.

1799 - 1878

Joesph Henry's research on electromagnetic induction is performed at the same time as Faraday's. He constructs the first motor; his work with electromagnets leads directly to the development of the telegraph.

1873

James Clerk Maxwell performs important research in three areas: color vision, molecular theory, and electromagnetic theory. The ideas underlying Maxwell's theories of electromagnetism describes the propagation of light waves in a vacuum.

1874

George Stoney develops a theory of the electron and estimates its mass.

1895

Wilhelm Röntgen discovers x rays.

1898

Marie and Pierre Curie separate radioactive elements.

1898

Joseph Thompson measures the electron, and puts forth his "plum-pudding" model of the atom -- that the atom is a slightly positive sphere with small, raisin-like negative electrons inside.