-
Discovery of the Electron
An English Physicist by the name of J. J. Thomson discovers the existence of subatomic particles with the electron. This went against contemporary scientific theory about matter, which proposed that atoms were the smallest unit of matter, and completely indivisible. -
Lord Kelvin on Science
Lord Kelvin, a prominent Irish physicist and mathematician said, "There is nothing new to be discovered in physics now, All that remains is more and more precise measurement." This quote embodies the optimistic attitude toward science at the turn of the century. -
Albert Einstein's Year of Discoveries.
Einstein wrote five history-making papers. He proposed the particle theory of light, developed a method to measure molecular dimensions, explained the long-puzzling Brownian motion, developed the theory of special relativity, and he finished his intellectual sprint by producing the world’s most famous equation, E = mc^2 This was a major point in the history of 20th century science. -
Bohr's Atomic Theory
Niels Bohr proposed a theory for the hydrogen atom based on quantum theory that energy is transferred only in certain well defined quantities. Electrons should move around the nucleus but only in prescribed orbits. When jumping from one orbit to another with lower energy, a light quantum is emitted. -
General Relativity
Albert Einstein updated his 1905 breakthrough of special relativity. The new, completed theory explained the force of gravitation and how it related to the other forces in nature. General relativity has great implications for astronomy and understanding of the greater universe. -
Many Galaxies
Edwin Powell Hubble, an American astronomer, proposes that the Milky Way is just one of many galaxies in the Universe. This was a foundational shift in the way people thought about the universe in a degree similar to Copernicus' heliocentric model of the universe. -
Schrodinger Equation
In 1925, Erwin Rudolf Josef Alexander Schrödinger, an Austrian-Irish physicist developed and introduced into use an equation modeling the state of an electron at a given point in time given certain parameters. This was used as evidence that electrons were waves, since that's what the function modeled. The wave-particle debate was one of the hottest topics in the new field of quantum mechanics.
