A timeline of atomic and subatomic physics.

Early beginnings

*In 6th century BCE, Acharya Kanada proposed that all matter must consist of indivisible particles and called them "anu". He proposes examples like ripening of fruit as the change in the number and types of atoms to create newer units. *430 BCE Democritus speculates about fundamental indivisible particles—calls them " atoms"

The beginning of chemistry

* 1766 Henry Cavendish discovers and studies hydrogen * 1778 Carl Scheele and Antoine Lavoisier discover that air is composed mostly of nitrogen and oxygen * 1781 Joseph Priestley creates water by igniting hydrogen and oxygen * 1800 William Nicholson and Anthony Carlisle use

electrolysis In chemistry and manufacturing, electrolysis is a technique that uses direct electric current (DC) to drive an otherwise non-spontaneous chemical reaction. Electrolysis is commercially important as a stage in the separation of elements from n ...

to separate water into hydrogen and oxygen * 1803

John Dalton John Dalton (; 5 or 6 September 1766 – 27 July 1844) was an English chemist, physicist and meteorologist. He is best known for introducing the atomic theory into chemistry, and for his research into colour blindness, which he had. Colour b ...

introduces atomic ideas into

chemistry Chemistry is the science, scientific study of the properties and behavior of matter. It is a natural science that covers the Chemical element, elements that make up matter to the chemical compound, compounds made of atoms, molecules and ions ...

and states that matter is composed of atoms of different weights * 1805 (approximate time) Thomas Young conducts the

double-slit experiment In modern physics, the double-slit experiment is a demonstration that light and matter can display characteristics of both classically defined waves and particles; moreover, it displays the fundamentally probabilistic nature of quantum mechanics ...

with light * 1811 Amedeo Avogadro claims that equal volumes of gases should contain equal numbers of molecules * 1832 Michael Faraday states his laws of electrolysis * 1871 Dmitri Mendeleyev systematically examines the

periodic table The periodic table, also known as the periodic table of the (chemical) elements, is a rows and columns arrangement of the chemical elements. It is widely used in chemistry, physics, and other sciences, and is generally seen as an icon of ch ...

and predicts the existence of

gallium Gallium is a chemical element with the symbol Ga and atomic number 31. Discovered by French chemist Paul-Émile Lecoq de Boisbaudran in 1875, Gallium is in group 13 of the periodic table and is similar to the other metals of the group (aluminiu ...

, scandium, and

germanium Germanium is a chemical element with the symbol Ge and atomic number 32. It is lustrous, hard-brittle, grayish-white and similar in appearance to silicon. It is a metalloid in the carbon group that is chemically similar to its group neighbors s ...

* 1873 Johannes van der Waals introduces the idea of weak attractive forces between molecules * 1885 Johann Balmer finds a mathematical expression for observed hydrogen line wavelengths * 1887 Heinrich Hertz discovers the photoelectric effect * 1894 Lord Rayleigh and William Ramsay discover argon by spectroscopically analyzing the gas left over after nitrogen and oxygen are removed from air * 1895 William Ramsay discovers terrestrial helium by spectroscopically analyzing gas produced by decaying uranium * 1896

Antoine Becquerel Antoine Henri Becquerel (; 15 December 1852 – 25 August 1908) was a French engineer, physicist, Nobel laureate, and the first person to discover evidence of radioactivity. For work in this field he, along with Marie Skłodowska-Curie and Pi ...

discovers the radioactivity of uranium * 1896 Pieter Zeeman studies the splitting of sodium D lines when sodium is held in a flame between strong magnetic poles * 1897 Emil Wiechert, Walter Kaufmann and J.J. Thomson discover the electron * 1898 Marie and Pierre Curie discovered the existence of the radioactive elements radium and polonium in their research of pitchblende * 1898 William Ramsay and Morris Travers discover

neon Neon is a chemical element with the symbol Ne and atomic number 10. It is a noble gas. Neon is a colorless, odorless, inert monatomic gas under standard conditions, with about two-thirds the density of air. It was discovered (along with krypton ...

, and negatively charged

beta particle A beta particle, also called beta ray or beta radiation (symbol β), is a high-energy, high-speed electron or positron emitted by the radioactive decay of an atomic nucleus during the process of beta decay. There are two forms of beta decay, β� ...

The age of quantum mechanics

* 1887

Heinrich Rudolf Hertz Heinrich Rudolf Hertz ( ; ; 22 February 1857 – 1 January 1894) was a German physicist who first conclusively proved the existence of the electromagnetic waves predicted by James Clerk Maxwell's equations of electromagnetism. The unit o ...

discovers the photoelectric effect that will play a very important role in the development of the quantum theory with

Einstein Albert Einstein ( ; ; 14 March 1879 – 18 April 1955) was a German-born theoretical physicist, widely acknowledged to be one of the greatest and most influential physicists of all time. Einstein is best known for developing the theory ...

's explanation of this effect in terms of ''

quanta Quanta is the plural of quantum. Quanta may also refer to: Organisations * Quanta Computer, a Taiwan-based manufacturer of electronic and computer equipment * Quanta Display Inc., a Taiwanese TFT-LCD panel manufacturer acquired by AU Optronic ...

'' of light * 1896 Wilhelm Conrad Röntgen discovers the X-rays while studying electrons in

plasma Plasma or plasm may refer to: Science * Plasma (physics), one of the four fundamental states of matter * Plasma (mineral), a green translucent silica mineral * Quark–gluon plasma, a state of matter in quantum chromodynamics Biology * Blood pla ...

;

scattering Scattering is a term used in physics to describe a wide range of physical processes where moving particles or radiation of some form, such as light or sound, are forced to deviate from a straight trajectory by localized non-uniformities (including ...

X-rays—that were considered as 'waves' of high-energy electromagnetic radiation—

Arthur Compton Arthur Holly Compton (September 10, 1892 – March 15, 1962) was an American physicist who won the Nobel Prize in Physics in 1927 for his 1923 discovery of the Compton effect, which demonstrated the particle nature of electromagnetic radia ...

will be able to demonstrate in 1922 the 'particle' aspect of electromagnetic radiation. * 1900

Paul Villard Paul Ulrich Villard (28 September 1860 – 13 January 1934) was a French chemist and physicist. He discovered gamma rays in 1900 while studying the radiation emanating from radium. Early research Villard was born in Saint-Germain-au-Mon ...

discovers gamma-rays while studying uranium decay * 1900 Johannes Rydberg refines the expression for observed hydrogen line wavelengths * 1900 Max Planck states his quantum hypothesis and blackbody radiation law * 1902 Philipp Lenard observes that maximum photoelectron energies are independent of illuminating intensity but depend on frequency * 1905 Albert Einstein explains the photoelectric effect * 1906 Charles Barkla discovers that each element has a characteristic X-ray and that the degree of penetration of these X-rays is related to the atomic weight of the element * 1909 Hans Geiger and Ernest Marsden discover large angle deflections of alpha particles by thin metal foils * 1909 Ernest Rutherford and Thomas Royds demonstrate that alpha particles are doubly ionized helium atoms * 1911 Ernest Rutherford explains the Geiger–Marsden experiment by invoking a nuclear atom model and derives the

Rutherford cross section Rutherford may refer to: Places Australia * Rutherford, New South Wales, a suburb of Maitland * Rutherford (Parish), New South Wales, a civil parish of Yungnulgra County Canada * Mount Rutherford, Jasper National Park * Rutherford, Edmonton ...

* 1911

Jean Perrin Jean Baptiste Perrin (30 September 1870 – 17 April 1942) was a French physicist who, in his studies of the Brownian motion of minute particles suspended in liquids ( sedimentation equilibrium), verified Albert Einstein’s explanation of this ...

proves the existence of

atoms Every atom is composed of a nucleus and one or more electrons bound to the nucleus. The nucleus is made of one or more protons and a number of neutrons. Only the most common variety of hydrogen has no neutrons. Every solid, liquid, gas, an ...

and

molecules A molecule is a group of two or more atoms held together by attractive forces known as chemical bonds; depending on context, the term may or may not include ions which satisfy this criterion. In quantum physics, organic chemistry, and bioche ...

with experimental work to test Einstein's theoretical explanation of Brownian motion * 1911

Ștefan Procopiu Ștefan Procopiu (; January 19, 1890 – August 22, 1972) was a Romanian physicist and a titular member of the Romanian Academy. Biography Procopiu was born in 1890 in Bârlad, Romania. His father, Emanoil Procopiu, was employed at the Bâr ...

measures the magnetic dipole moment of the electron * 1912

Max von Laue Max Theodor Felix von Laue (; 9 October 1879 – 24 April 1960) was a German physicist who received the Nobel Prize in Physics in 1914 for his discovery of the diffraction of X-rays by crystals. In addition to his scientific endeavors with cont ...

suggests using

crystal lattice In geometry and crystallography, a Bravais lattice, named after , is an infinite array of discrete points generated by a set of discrete translation operations described in three dimensional space by : \mathbf = n_1 \mathbf_1 + n_2 \mathbf_2 + n ...

s to diffract X-rays * 1912

Walter Friedrich Walter may refer to: People * Walter (name), both a surname and a given name * Little Walter, American blues harmonica player Marion Walter Jacobs (1930–1968) * Gunther (wrestler), Austrian professional wrestler and trainer Walter Hahn (born 19 ...

and

Paul Knipping Paul may refer to: *Paul (given name), a given name (includes a list of people with that name) *Paul (surname), a list of people People Christianity *Paul the Apostle (AD c.5–c.64/65), also known as Saul of Tarsus or Saint Paul, early Chris ...

diffract X-rays in zinc blende * 1913 William Henry Bragg and William Lawrence Bragg work out the

Bragg condition In physics and chemistry , Bragg's law, Wulff–Bragg's condition or Laue–Bragg interference, a special case of Laue diffraction X-ray crystallography is the experimental science determining the atomic and molecular structure of a crystal, in ...

for strong X-ray reflection * 1913 Henry Moseley shows that nuclear charge is the real basis for numbering the elements * 1913 Niels Bohr presents his quantum model of the atom * 1913 Robert Millikan measures the fundamental unit of electric charge * 1913 Johannes Stark demonstrates that strong electric fields will split the Balmer spectral line series of hydrogen * 1914 James Franck and Gustav Hertz observe atomic excitation * 1914 Ernest Rutherford suggests that the positively charged atomic nucleus contains

proton A proton is a stable subatomic particle, symbol , H+, or 1H+ with a positive electric charge of +1 ''e'' elementary charge. Its mass is slightly less than that of a neutron and 1,836 times the mass of an electron (the proton–electron mass ...

s * 1915

Arnold Sommerfeld Arnold Johannes Wilhelm Sommerfeld, (; 5 December 1868 – 26 April 1951) was a German theoretical physicist who pioneered developments in atomic and quantum physics, and also educated and mentored many students for the new era of theoretica ...

develops a modified Bohr atomic model with elliptic orbits to explain relativistic fine structure * 1916

Gilbert N. Lewis Gilbert Newton Lewis (October 23 or October 25, 1875 – March 23, 1946) was an American physical chemist and a Dean of the College of Chemistry at University of California, Berkeley. Lewis was best known for his discovery of the covalent bond a ...

and

Irving Langmuir Irving Langmuir (; January 31, 1881 – August 16, 1957) was an American chemist, physicist, and engineer. He was awarded the Nobel Prize in Chemistry in 1932 for his work in surface chemistry. Langmuir's most famous publication is the 1919 art ...

formulate an electron shell model of chemical bonding * 1917 Albert Einstein introduces the idea of stimulated radiation emission * 1918 Ernest Rutherford notices that, when alpha particles were shot into nitrogen gas, his

scintillation detector Scintillation can refer to: *Scintillation (astronomy), atmospheric effects which influence astronomical observations *Interplanetary scintillation, fluctuations of radio waves caused by the solar wind *Scintillation (physics), a flash of light pro ...

s showed the signatures of hydrogen nuclei. * 1921 Alfred Landé introduces the Landé g-factor * 1922

studies X-ray photon

by electrons demonstrating the 'particle' aspect of electromagnetic radiation. * 1922 Otto Stern and Walther Gerlach show " spin quantization" * 1923

Lise Meitner Elise Meitner ( , ; 7 November 1878 – 27 October 1968) was an Austrian-Swedish physicist who was one of those responsible for the discovery of the element protactinium and nuclear fission. While working at the Kaiser Wilhelm Institute on rad ...

discovers what is now referred to as the Auger process * 1924 Louis de Broglie suggests that electrons may have wavelike properties in addition to their 'particle' properties; the '' wave–particle duality'' has been later extended to all fermions and bosons. * 1924 John Lennard-Jones proposes a semiempirical interatomic force law * 1924

Santiago Antúnez de Mayolo Santiago Antúnez de Mayolo was born on 10 January 1887 in the country estate of Vista Bella, province of Aija, Peru, department of Áncash. He was an engineer, physicist and mathematician. Early years He studied at Colegio Nacional de la Li ...

proposes a neutron. * 1924

Satyendra Bose Satyendra Nath Bose (; 1 January 1894 – 4 February 1974) was a Bengali mathematician and physicist specializing in theoretical physics. He is best known for his work on quantum mechanics in the early 1920s, in developing the foundation for ...

and Albert Einstein introduce Bose–Einstein statistics * 1925 Wolfgang Pauli states the quantum exclusion principle for electrons * 1925 George Uhlenbeck and Samuel Goudsmit postulate electron

spin Spin or spinning most often refers to: * Spinning (textiles), the creation of yarn or thread by twisting fibers together, traditionally by hand spinning * Spin, the rotation of an object around a central axis * Spin (propaganda), an intentionally b ...

* 1925 Pierre Auger discovers the Auger process (2 years after

) * 1925 Werner Heisenberg,

Max Born Max Born (; 11 December 1882 – 5 January 1970) was a German 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 n ...

, and Pascual Jordan formulate quantum matrix mechanics * 1926 Erwin Schrödinger states his nonrelativistic quantum wave equation and formulates quantum wave mechanics * 1926 Erwin Schrödinger proves that the wave and matrix formulations of quantum theory are mathematically equivalent * 1926

Oskar Klein Oskar Benjamin Klein (; 15 September 1894 – 5 February 1977) was a Swedish theoretical physicist. Biography Klein was born in Danderyd outside Stockholm, son of the chief rabbi of Stockholm, Gottlieb Klein from Humenné in Kingdom of Hungary ...

and Walter Gordon state their relativistic quantum wave equation, now the Klein–Gordon equation * 1926

Enrico Fermi Enrico Fermi (; 29 September 1901 – 28 November 1954) was an Italian (later naturalized American) physicist and the creator of the world's first nuclear reactor, the Chicago Pile-1. He has been called the "architect of the nuclear age" and ...

discovers the spin–statistics connection, for particles that are now called 'fermions', such as the electron (of spin-1/2). * 1926 Paul Dirac introduces

Fermi–Dirac statistics Fermi–Dirac statistics (F–D statistics) is a type of quantum statistics that applies to the physics of a system consisting of many non-interacting, identical particles that obey the Pauli exclusion principle. A result is the Fermi–Dirac di ...

* 1926

introduces the term "''photon''", thought by him to be "''the carrier of radiant energy.''" * 1927 Clinton Davisson,

Lester Germer Lester Halbert Germer (October 10, 1896 – October 3, 1971) was an American physicist. With Clinton Davisson, he proved the wave-particle duality of matter in the Davisson–Germer experiment, which was important to the development of the elec ...

, and George Paget Thomson confirm the wavelike nature of electrons * 1927 Werner Heisenberg states the quantum uncertainty principle * 1927

interprets the probabilistic nature of wavefunctions * 1927 Walter Heitler and Fritz London introduce the concepts of

valence bond theory In chemistry, valence bond (VB) theory is one of the two basic theories, along with molecular orbital (MO) theory, that were developed to use the methods of quantum mechanics to explain chemical bonding. It focuses on how the atomic orbitals of ...

and apply it to the hydrogen molecule. * 1927 Thomas and

Fermi Enrico Fermi (; 29 September 1901 – 28 November 1954) was an Italian (later naturalized American) physicist and the creator of the world's first nuclear reactor, the Chicago Pile-1. He has been called the "architect of the nuclear age" and ...

develop the

Thomas–Fermi model The Thomas–Fermi (TF) model, named after Llewellyn Thomas and Enrico Fermi, is a quantum mechanical theory for the electronic structure of many-body systems developed semiclassically shortly after the introduction of the Schrödinger equat ...

* 1927

and Robert Oppenheimer introduce the Born–Oppenheimer approximation * 1928

Chandrasekhara Raman Sir Chandrasekhara Venkata Raman (; 7 November 188821 November 1970) was an Indian physicist known for his work in the field of light scattering. Using a spectrograph that he developed, he and his student K. S. Krishnan discovered that whe ...

studies optical photon scattering by electrons * 1928 Paul Dirac states his relativistic electron quantum wave equation * 1928

Charles G. Darwin Sir Charles Galton Darwin (19 December 1887 – 31 December 1962) was an English physicist who served as director of the National Physical Laboratory (NPL) during the Second World War. He was a son of the mathematician George Howard Darwin ...

and Walter Gordon solve the Dirac equation for a Coulomb potential * 1928 Friedrich Hund and Robert S. Mulliken introduce the concept of molecular orbital * 1929

discovers the

Klein paradox In 1929, physicist Oskar Klein obtained a surprising result by applying the Dirac equation to the familiar problem of electron scattering from a potential barrier. In nonrelativistic quantum mechanics, electron tunneling into a barrier is observe ...

* 1929 Oskar Klein and Yoshio Nishina derive the Klein–Nishina cross section for high energy photon scattering by electrons * 1929 Nevill Mott derives the Mott cross section for the Coulomb scattering of relativistic electrons * 1930 Paul Dirac introduces electron hole theory * 1930 Erwin Schrödinger predicts the zitterbewegung motion * 1930 Fritz London explains van der Waals forces as due to the interacting fluctuating dipole moments between molecules * 1931 John Lennard-Jones proposes the Lennard-Jones interatomic potential * 1931 Irène Joliot-Curie and

Frédéric Joliot Frédéric and Frédérick are the French versions of the common male given name Frederick. They may refer to: In artistry: * Frédéric Back, Canadian award-winning animator * Frédéric Bartholdi, French sculptor * Frédéric Bazille, Impress ...

observe but misinterpret neutron scattering in paraffin * 1931 Wolfgang Pauli puts forth the neutrino hypothesis to explain the apparent violation of

energy conservation Energy conservation is the effort to reduce wasteful energy consumption by using fewer energy services. This can be done by using energy more effectively (using less energy for continuous service) or changing one's behavior to use less service (f ...

in beta decay * 1931

Linus Pauling Linus Carl Pauling (; February 28, 1901August 19, 1994) was an American chemist, biochemist, chemical engineer, peace activist, author, and educator. He published more than 1,200 papers and books, of which about 850 dealt with scientific top ...

discovers resonance bonding and uses it to explain the high stability of symmetric planar molecules * 1931 Paul Dirac shows that charge quantization can be explained if magnetic monopoles exist * 1931 Harold Urey discovers deuterium using evaporation concentration techniques and spectroscopy * 1932 John Cockcroft and Ernest Walton split lithium and

boron Boron is a chemical element with the symbol B and atomic number 5. In its crystalline form it is a brittle, dark, lustrous metalloid; in its amorphous form it is a brown powder. As the lightest element of the ''boron group'' it has th ...

nuclei using proton bombardment * 1932 James Chadwick discovers the neutron * 1932 Werner Heisenberg presents the proton–neutron model of the nucleus and uses it to explain isotopes * 1932

Carl D. Anderson Carl David Anderson (September 3, 1905 – January 11, 1991) was an American physicist. He is best known for his discovery of the positron in 1932, an achievement for which he received the 1936 Nobel Prize in Physics, and of the muon in 1936. ...

discovers the

positron The positron or antielectron is the antiparticle or the antimatter counterpart of the electron. It has an electric charge of +1 '' e'', a spin of 1/2 (the same as the electron), and the same mass as an electron. When a positron collides ...

* 1933 Ernst Stueckelberg (1932), Lev Landau (1932), and Clarence Zener discover the Landau–Zener transition * 1933 Max Delbrück suggests that quantum effects will cause photons to be scattered by an external electric field * 1934 Irène Joliot-Curie and

bombard aluminium atoms with alpha particles to create artificially radioactive phosphorus-30 * 1934 Leó Szilárd realizes that

nuclear chain reaction In nuclear physics, a nuclear chain reaction occurs when one single nuclear reaction causes an average of one or more subsequent nuclear reactions, thus leading to the possibility of a self-propagating series of these reactions. The specific nu ...

s may be possible * 1934

publishes a very successful model of beta decay in which neutrinos were produced. * 1934 Lev Landau tells Edward Teller that non-linear molecules may have vibrational modes which remove the

degeneracy Degeneracy, degenerate, or degeneration may refer to: Arts and entertainment * ''Degenerate'' (album), a 2010 album by the British band Trigger the Bloodshed * Degenerate art, a term adopted in the 1920s by the Nazi Party in Germany to descri ...

of an orbitally degenerate state (

Jahn–Teller effect The Jahn–Teller effect (JT effect or JTE) is an important mechanism of spontaneous symmetry breaking in molecular and solid-state systems which has far-reaching consequences in different fields, and is responsible for a variety of phenomena in sp ...

) * 1934

suggests bombarding uranium atoms with neutrons to make a 93 proton element * 1934 Pavel Cherenkov reports that light is emitted by relativistic particles traveling in a nonscintillating liquid * 1935 Hideki Yukawa presents a theory of the nuclear force and predicts the scalar meson * 1935 Albert Einstein, Boris Podolsky, and Nathan Rosen put forth the EPR paradox * 1935 Henry Eyring develops the transition state theory * 1935 Niels Bohr presents his analysis of the EPR paradox * 1936 Alexandru Proca formulates the relativistic quantum field equations for a massive vector meson of spin-1 as a basis for nuclear forces * 1936 Eugene Wigner develops the theory of neutron absorption by atomic nuclei * 1936 Hermann Arthur Jahn and Edward Teller present their systematic study of the symmetry types for which the

is expected * 1937 Carl Anderson proves experimentally the existence of the pion predicted by Yukawa's theory. * 1937

Hans Hellmann Hans Gustav Adolf Hellmann (14 October 1903 – 29 May 1938) was a German theoretical physicist. Biography Hellmann was born in Wilhelmshaven, Prussian Hanover. He began studying electrical engineering in University of Stuttgart, Stuttgart, b ...

finds the Hellmann–Feynman theorem * 1937 Seth Neddermeyer, Carl Anderson, J.C. Street, and E.C. Stevenson discover

muon A muon ( ; from the Greek letter mu (μ) used to represent it) is an elementary particle similar to the electron, with an electric charge of −1 '' e'' and a spin of , but with a much greater mass. It is classified as a lepton. As wi ...

s using cloud chamber measurements of cosmic rays * 1939 Richard Feynman finds the Hellmann–Feynman theorem * 1939 Otto Hahn and Fritz Strassmann bombard uranium salts with thermal neutrons and discover

barium Barium is a chemical element with the symbol Ba and atomic number 56. It is the fifth element in group 2 and is a soft, silvery alkaline earth metal. Because of its high chemical reactivity, barium is never found in nature as a free element. Th ...

among the reaction products * 1939

and Otto Robert Frisch determine that

nuclear fission Nuclear fission is a reaction in which the nucleus of an atom splits into two or more smaller nuclei. The fission process often produces gamma photons, and releases a very large amount of energy even by the energetic standards of radio ...

is taking place in the Hahn–Strassmann experiments * 1942

makes the first controlled nuclear chain reaction * 1942 Ernst Stueckelberg introduces the propagator to positron theory and interprets positrons as negative energy electrons moving backwards through spacetime * 1947 Willis Lamb and Robert Retherford measure the Lamb–Retherford shift * 1947

Cecil Powell Cecil Frank Powell, FRS (5 December 1903 – 9 August 1969) was a British physicist, and Nobel Prize in Physics laureate for heading the team that developed the photographic method of studying nuclear processes and for the resulting discovery of ...

, César Lattes, and Giuseppe Occhialini discover the pi meson by studying cosmic ray tracks * 1947 Richard Feynman presents his propagator approach to quantum electrodynamics * 1948 Hendrik Casimir predicts a rudimentary attractive Casimir force on a parallel plate capacitor * 1951 Martin Deutsch discovers positronium * 1952 David Bohm propose his interpretation of quantum mechanics * 1953 Robert Wilson observes Delbruck scattering of 1.33 MeV gamma-rays by the electric fields of lead nuclei * 1953 Charles H. Townes, collaborating with J. P. Gordon, and H. J. Zeiger, builds the first ammonia maser * 1954

Chen Ning Yang Yang Chen-Ning or Chen-Ning Yang (; born 1 October 1922), also known as C. N. Yang or by the English name Frank Yang, is a Chinese theoretical physicist who made significant contributions to statistical mechanics, integrable systems, gauge the ...

and Robert Mills investigate a theory of hadronic isospin by demanding local gauge invariance under isotopic spin space rotations, the first non-Abelian

gauge theory In physics, a gauge theory is a type of field theory in which the Lagrangian (and hence the dynamics of the system itself) does not change (is invariant) under local transformations according to certain smooth families of operations (Lie groups) ...

* 1955

Owen Chamberlain Owen Chamberlain (July 10, 1920 – February 28, 2006) was an American physicist who shared with Emilio Segrè the Nobel Prize in Physics for the discovery of the antiproton, a sub-atomic antiparticle. Biography Born in San Francisco, Cal ...

, Emilio Segrè, Clyde Wiegand, and

Thomas Ypsilantis Thomas John Ypsilantis ( el, Θωμάς Υψηλάντης, link=no; June 24, 1928 – August 16, 2000) was an American physicist of Greek descent. Ypsilantis was known for the co-discovery of the antiproton in 1955, along with Owen Chamberlai ...

discover the antiproton * 1956 Frederick Reines and Clyde Cowan detect antineutrino * 1956

and Tsung Lee propose

parity violation In physics, a parity transformation (also called parity inversion) is the flip in the sign of ''one'' spatial coordinate. In three dimensions, it can also refer to the simultaneous flip in the sign of all three spatial coordinates (a point refle ...

by the weak nuclear force * 1956 Chien Shiung Wu discovers parity violation by the weak force in decaying cobalt * 1957 Gerhart Luders proves the CPT theorem * 1957 Richard Feynman, Murray Gell-Mann, Robert Marshak, and

E.C.G. Sudarshan Ennackal Chandy George Sudarshan (also known as E. C. G. Sudarshan; 16 September 1931 – 13 May 2018) was an Indian American theoretical physicist and a professor at the University of Texas. Sudarshan has been credited with numerous contri ...

propose a vector/axial vector (VA)

Lagrangian Lagrangian may refer to: Mathematics * Lagrangian function, used to solve constrained minimization problems in optimization theory; see Lagrange multiplier ** Lagrangian relaxation, the method of approximating a difficult constrained problem with ...

for weak interactions. * 1958 Marcus Sparnaay experimentally confirms the Casimir effect * 1959 Yakir Aharonov and David Bohm predict the Aharonov–Bohm effect * 1960 R.G. Chambers experimentally confirms the Aharonov–Bohm effect * 1961 Murray Gell-Mann and Yuval Ne'eman discover the Eightfold Way patterns, the SU(3) group * 1961 Jeffrey Goldstone considers the breaking of global phase symmetry * 1962 Leon Lederman shows that the electron neutrino is distinct from the muon neutrino * 1963 Eugene Wigner discovers the fundamental roles played by quantum symmetries in atoms and molecules

The formation and successes of the Standard Model

* 1964 Murray Gell-Mann and George Zweig propose the quark/aces model Frank Wilczek (1999)
Quantum field theory
, ''Reviews of Modern Physics'' 71: S83–S95. Also doi=10.1103/Rev. Mod. Phys. 71. * 1964 Peter Higgs considers the breaking of local phase symmetry * 1964 John Stewart Bell shows that all local hidden variable theories must satisfy Bell's inequality * 1964

Val Fitch Val Logsdon Fitch (March 10, 1923 – February 5, 2015) was an American nuclear physicist who, with co-researcher James Cronin, was awarded the 1980 Nobel Prize in Physics for a 1964 experiment using the Alternating Gradient Synchrotron at Broo ...

and

James Cronin James Watson Cronin (September 29, 1931 – August 25, 2016) was an American particle physicist. Cronin was born in Chicago, Illinois, and attended Southern Methodist University in Dallas, Texas. He and co-researcher Val Logsdon Fitch were aw ...

observe CP violation by the weak force in the decay of K mesons * 1967 Steven Weinberg puts forth his electroweak model of

lepton In particle physics, a lepton is an elementary particle of half-integer spin ( spin ) that does not undergo strong interactions. Two main classes of leptons exist: charged leptons (also known as the electron-like leptons or muons), and neutr ...

sWeinberg, Steven; The Quantum Theory of Fields: Modern Applications (vol. II), Cambridge University Press:Cambridge, U.K. (1996) , pp. 489. * 1969 John Clauser,

Michael Horne Michael Rex Horne OBE FREng, FRS (29 December 1921 – 6 January 2000) was an English structural engineer, scientist and academic who pioneered the theory of the Plastic Design of Structures. Early life and education Horne was born i ...

, Abner Shimony and Richard Holt propose a polarization correlation test of Bell's inequality * 1970 Sheldon Glashow, John Iliopoulos, and Luciano Maiani propose the charm quark * 1971 Gerard 't Hooft shows that the Glashow-Salam-Weinberg electroweak model can be renormalized * 1972

Stuart Freedman Stuart Jay Freedman (January 13, 1944 – November 10, 2012) was an American physicist, known for his work on a Bell test experiment with John Clauser at the University of California, Berkeley as well as for his contributions to nuclear and part ...

and John Clauser perform the first polarization correlation test of Bell's inequality * 1973 David Politzer and Frank Anthony Wilczek propose the asymptotic freedom of quarks * 1974 Burton Richter and

Samuel Ting Samuel Chao Chung Ting (, born January 27, 1936) is a Chinese-American physicist who, with Burton Richter, received the Nobel Prize in 1976 for discovering the subatomic J/ψ particle. More recently he has been the principal investigator in res ...

discover the J/ψ particle implying the existence of the charm quark * 1974 Robert J. Buenker and

Sigrid D. Peyerimhoff Sigrid Doris Peyerimhoff (born 12 January 1937, in Rottweil) is a theoretical chemist and Emeritus Professor at the Institute of Physical and Theoretical Chemistry, University of Bonn, Germany. Education After completing her '' abitur'', Peyerim ...

introduce the multireference configuration interaction method. * 1975 Martin Perl discovers the tau lepton * 1977 Steve Herb finds the upsilon resonance implying the existence of the beauty/bottom quark * 1982 Alain Aspect, J. Dalibard, and G. Roger perform a polarization correlation test of Bell's inequality that rules out conspiratorial polarizer communication * 1983 Carlo Rubbia, Simon van der Meer, and the CERN UA-1 collaboration find the W and Z intermediate vector bosons * 1989 The Z intermediate vector boson resonance width indicates three quark-lepton generations * 1994 The

CERN The European Organization for Nuclear Research, known as CERN (; ; ), is an intergovernmental organization that operates the largest particle physics laboratory in the world. Established in 1954, it is based in a northwestern suburb of Gene ...

LEAR Crystal Barrel Experiment justifies the existence of glueballs ( exotic meson). * 1995 The D0 and CDF experiments at the Fermilab Tevatron discover the top quark. * 1998 Super-Kamiokande (Japan) observes evidence for neutrino oscillations, implying that at least one neutrino has mass. * 1999 Ahmed Zewail wins the Nobel prize in chemistry for his work on

femtochemistry Femtochemistry is the area of physical chemistry that studies chemical reactions on extremely short timescales (approximately 10−15 seconds or one femtosecond, hence the name) in order to study the very act of atoms within molecules (reactants ...

for atoms and molecules. * 2001 The Sudbury Neutrino Observatory (Canada) confirms the existence of neutrino oscillations. * 2005 At the

RHIC The Relativistic Heavy Ion Collider (RHIC ) is the first and one of only two operating heavy-ion colliders, and the only spin-polarized proton collider ever built. Located at Brookhaven National Laboratory (BNL) in Upton, New York, and used by a ...

accelerator of Brookhaven National Laboratory they have created a quark–gluon liquid of very low viscosity, perhaps the quark–gluon plasma * 2010 The

Large Hadron Collider The Large Hadron Collider (LHC) is the world's largest and highest-energy particle collider. It was built by the European Organization for Nuclear Research (CERN) between 1998 and 2008 in collaboration with over 10,000 scientists and hundred ...

begins operation with the primary goal of searching for the

Higgs boson The Higgs boson, sometimes called the Higgs particle, is an elementary particle in the Standard Model of particle physics produced by the quantum excitation of the Higgs field, one of the fields in particle physics theory. In the Stand ...

. * 2012

announces the discovery of a new particle with properties consistent with the

of the

Standard Model The Standard Model of particle physics is the theory describing three of the four known fundamental forces (electromagnetism, electromagnetic, weak interaction, weak and strong interactions - excluding gravity) in the universe and classifying a ...

after experiments at the

Quantum field theories beyond the Standard Model

* 2000 Steven Weinberg. Supersymmetry and Quantum Gravity. *2003 Leonid Vainerman. Quantum groups, Hopf algebras and quantum field applications.Leonid Vainerman, editor. 2003. ''Locally Compact Quantum Groups and Groupoids''. ''Proceed. Theor. Phys. Strassbourg in 2002'', Walter de Gruyter: Berlin and New York * Noncommutative quantum field theory * M.R. Douglas and N. A. Nekrasov (2001)
Noncommutative field theory
" Rev. Mod. Phys. 73: 977–1029. * Szabo, R. J. (2003)
Quantum Field Theory on Noncommutative Spaces
" ''Physics Reports'' 378: 207–99. An expository article on noncommutative quantum field theories.
Noncommutative quantum field theory, see statistics
on arxiv.org * Seiberg, N. and E. Witten (1999)
String Theory and Noncommutative Geometry
" ''Journal of High Energy Physics'' *

Sergio Doplicher Sergio Doplicher (born 30 December 1940) is an Italian mathematical physicist, who mainly dealt with the mathematical foundations of quantum field theory and quantum gravity. Biography Sergio Doplicher graduated in Physics at the Sapienza Univ ...

, Klaus Fredenhagen and John Roberts, Sergio Doplicher, Klaus Fredenhagen, John E. Roberts (1995
The quantum structure of spacetime at the Planck scale and quantum fields
" ''Commun. Math. Phys''. 172: 187–220. * Alain Connes (1994)
Noncommutative geometry.
' Academic Press. . * -------- (1995) "Noncommutative geometry and reality", ''J. Math. Phys.'' 36: 6194. * -------- (1996)
Gravity coupled with matter and the foundation of noncommutative geometry
" ''Comm. Math. Phys.'' 155: 109. * -------- (2006)
Noncommutative geometry and physics
" * -------- and M. Marcolli,
Noncommutative Geometry: Quantum Fields and Motives.
' American Mathematical Society (2007). * Chamseddine, A., A. Connes (1996)
The spectral action principle
" ''Comm. Math. Phys.'' 182: 155. * Chamseddine, A., A. Connes, M. Marcolli (2007)
Gravity and the Standard Model with neutrino mixing
" ''Adv. Theor. Math. Phys.'' 11: 991. * Jureit, Jan-H., Thomas Krajewski, Thomas Schücker, and Christoph A. Stephan (2007)
On the noncommutative standard model
" ''Acta Phys. Polon.'' B38: 3181–3202. *Schücker, Thomas (2005)
Forces from Connes's geometry.
' Lecture Notes in Physics 659, Springer. *

Noncommutative standard model In theoretical particle physics, the non-commutative Standard Model (best known as Spectral Standard Model ), is a model based on noncommutative geometry that unifies a modified form of general relativity with the Standard Model (extended with ...

* Noncommutative geometry

References

External links

Alain Connes official website
wit
downloadable papers.

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