## Max Planck

Max Karl Ernst Ludwig Planck, (German; April 23, 1858 – October 4, 1947) Theoretical physicist who originated quantum theory, which won him the Nobel Prize in Physics in 1918. Planck made many contributions to theoretical physics, but his fame rests primarily on his role as originator of the quantum theory. This theory revolutionized human understanding of atomic and subatomic processes, just as Albert Einstein’s theory of relativity revolutionized the understanding of space and time. Together they constitute the fundamental theories of 20th-century physics. Read more...

## Enrico Fermi

Enrico Fermi (Italian; 29 September 1901 – 28 November 1954) Physicist, best known for his work on Chicago Pile (the first nuclear reactor), and for his contributions to the development of quantum theory, nuclear and particle physics, and statistical mechanics. He is one of the men referred to as the "father of the atomic bomb." Fermi held several patents related to the use of nuclear power, and was awarded the 1938 Nobel Prize in Physics for his work on induced radioactivity by neutron bombardment and the discovery of transuranic elements. He was widely regarded as one of the very few physicists to excel both theoretically and experimentally. Read more...

## Wolfgang Pauli

Wolfgang Ernst Pauli (Austrian; 25 April 1900 – 15 December 1958) Theoretical physicist and one of the pioneers of quantum physics. In 1945, after having been nominated by Albert Einstein, Pauli received the Nobel Prize in Physics for his "decisive contribution through his discovery of a new law of Nature, the exclusion principle or Pauli principle." The discovery involved spin theory, which is the basis of a theory of the structure of matter. Read more...

## Niels Bohr

Niels Henrik David Bohr (Danish; 7 October 1885 – 18 November 1962) Physicist who made foundational contributions to understanding atomic structure and quantum theory, for which he received the Nobel Prize in Physics in 1922. Bohr was also a philosopher and a promoter of scientific research. Bohr developed the Bohr model of the atom, in which he proposed that energy levels of electrons are discrete, and that the electrons revolve in stable orbits around the atomic nucleus, but can jump from one energy level (or orbit) to another. Although the Bohr model has been supplanted by other models, its underlying principles remain valid. He conceived the principle of complementarity: that items could be separately analysed in terms of contradictory properties, like behaving as a wave or a stream of particles. The notion of complementarity dominated Bohr's thinking in both science and philosophy. Read more...

## Max Born

Max Born (German-British; 11 December 1882 – 5 January 1970) Physicist and mathematician who was instrumental in the development of quantum mechanics. He also made contributions to solid-state physics and optics and supervised the work of a number of notable physicists in the 1920s and 30s. Born won the 1954 Nobel Prize in Physics for his "fundamental research in Quantum Mechanics." Read more...

## Erwin Schrödinger

Erwin Rudolf Josef Alexander Schrödinger (Austrian; 12 August 1887 – 4 January 1961) Nobel Prize-winning physicist who developed a number of fundamental results in the field of quantum theory, which formed the basis of wave mechanics: he formulated the wave equation (stationary and time-dependent Schrödinger equation) and revealed the identity of his development of the formalism and matrix mechanics. Schrödinger proposed an original interpretation of the physical meaning of the wave function and in subsequent years repeatedly criticized the conventional Copenhagen interpretation of quantum mechanics (using e.g. the paradox of Schrödinger's cat). Read more...

## Werner Heisenberg

Werner Karl Heisenberg (German; 5 December 1901 – 1 February 1976) Theoretical physicist and one of the key creators of quantum mechanics. He published his work in 1925 in a breakthrough paper. In the subsequent series of papers with Max Born and Pascual Jordan, during the same year, this matrix formulation of quantum mechanics was substantially elaborated. In 1927 he published his uncertainty principle, upon which he built his philosophy and for which he is best known. Heisenberg was awarded the Nobel Prize in Physics for 1932 "for the creation of quantum mechanics". He also made important contributions to the theories of the hydrodynamics of turbulent flows, the atomic nucleus, ferromagnetism, cosmic rays, and subatomic particles, and he was instrumental in planning the first West German nuclear reactor at Karlsruhe, together with a research reactor in Munich, in 1957. Read more...

## Satyendra Nath Bose

Satyendra Nath Bose (Bengali India; 1 January 1894 – 4 February 1974) Physicist specializing in mathematical physics. He was born in Calcutta. He is best known for his work on quantum mechanics in the early 1920s, providing the foundation for Bose–Einstein statistics and the theory of the Bose–Einstein condensate. A Fellow of the Royal Society, the Government of India awarded him India's second highest civilian award, the Padma Vibhushan in 1954. The class of particles that obey Bose–Einstein statistics, bosons, were named after him by Paul Dirac. Read more...

## Albert Einstein

Albert Einstein (German; 14 March 1879 – 18 April 1955) was a German-born theoretical physicist. He developed:

General and Special relativity, which addressed the motion of bodies in uniform and accelerated motion as well leading to a more precise understanding of the nature of gravity. He is best known for his mass–energy equivalence formula E = mc2 (which has been dubbed "the world's most famous equation"). He received the 1921 Nobel Prize in Physics "for his services to theoretical physics, and especially for his discovery of the law of the Photoelectric Effect". The latter was pivotal in establishing quantum theory. Read more...

## Pascual Jordan

Ernst Pascual Jordan (German; 18 October 1902 – 31 July 1980) was a theoretical and mathematical physicist who made significant contributions to quantum mechanics and quantum field theory. He contributed much to the mathematical form of matrix mechanics, and developed canonical anticommutation relations for fermions. While the Jordan algebra he invented is not routinely employed in quantum mechanics, it has found other mathematical applications and is still used in studying the mathematical and conceptual foundations of quantum theory. Read more...