Portal:Physics

The Physics Portal

The expansion of the universe according to the Big Bang theory in physics

Physics is the scientific study of matter, its fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. Physics is one of the most fundamental scientific disciplines. A scientist who specializes in the field of physics is called a physicist.

Physics is one of the oldest academic disciplines. Over much of the past two millennia, physics, chemistry, biology, and certain branches of mathematics were a part of natural philosophy, but during the Scientific Revolution in the 17th century, these natural sciences branched into separate research endeavors. Physics intersects with many interdisciplinary areas of research, such as biophysics and quantum chemistry, and the boundaries of physics are not rigidly defined. New ideas in physics often explain the fundamental mechanisms studied by other sciences and suggest new avenues of research in these and other academic disciplines such as mathematics and philosophy.

Advances in physics often enable new technologies. For example, advances in the understanding of electromagnetism, solid-state physics, and nuclear physics led directly to the development of technologies that have transformed modern society, such as television, computers, domestic appliances, and nuclear weapons; advances in thermodynamics led to the development of industrialization; and advances in mechanics inspired the development of calculus. (Full article...)

Featured article -

This is a Featured article, which represents some of the best content on English Wikipedia.

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In classical mechanics, the Laplace–Runge–Lenz (LRL) vector is a vector used chiefly to describe the shape and orientation of the orbit of one astronomical body around another, such as a binary star or a planet revolving around a star. For two bodies interacting by Newtonian gravity, the LRL vector is a constant of motion, meaning that it is the same no matter where it is calculated on the orbit; equivalently, the LRL vector is said to be conserved. More generally, the LRL vector is conserved in all problems in which two bodies interact by a central force that varies as the inverse square of the distance between them; such problems are called Kepler problems.

The hydrogen atom is a Kepler problem, since it comprises two charged particles interacting by Coulomb's law of electrostatics, another inverse-square central force. The LRL vector was essential in the first quantum mechanical derivation of the spectrum of the hydrogen atom, before the development of the Schrödinger equation. However, this approach is rarely used today. (Full article...)

Did you know -

Gold leaf processing at a workshop in Kanazawa, Japan

• ... that gold leaf is about 500 atoms thick?

• ... that, in the Large Hadron Collider, protons move at 99.9999991% the speed of light when accelerated with the energy of 7 TeV?

• ... that, at a speed of 299,792,458 m/s, light can travel from the Earth to the Moon in 1.2 seconds?

Selected image -

A ferrofluid on a glass plate, being affected by a rare-earth magnet

Image credit: Gregory Maxwell

A ferrofluid is a liquid which becomes strongly polarised in the presence of a magnetic field. Ferrofluids are composed of nanoscale ferromagnetic particles suspended in a carrier fluid, usually an organic solvent or water. The ferromagnetic nano-particles are coated with a surfactant to prevent their agglomeration (due to van der Waals and magnetic forces). Although the name may suggest otherwise, ferrofluids do not display ferromagnetism, since they do not retain magnetisation in the absence of an externally applied field. In fact, ferrofluids display paramagnetism, and are often referred as being "superparamagnetic" due to their large magnetic susceptibility. True ferromagnetic fluids are difficult to create at present.

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Good articles -

These are Good articles, which meet a core set of high editorial standards.

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  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 Brookhaven National Laboratory that proved that certain subatomic reactions do not adhere to fundamental symmetry principles. Specifically, they proved, by examining the decay of K-mesons, that a reaction run in reverse does not retrace the path of the original reaction, which showed that the reactions of subatomic particles are not indifferent to time. Thus the phenomenon of CP violation was discovered. This demolished the faith that physicists had that natural laws were governed by symmetry.
  
  Born on a cattle ranch near Merriman, Nebraska, Fitch was drafted into the U.S. Army during World War II, and worked on the Manhattan Project at the Los Alamos Laboratory in New Mexico. He later graduated from McGill University, and completed his PhD in physics in 1954 at Columbia University. He was a member of the faculty at Princeton University from 1954 until his retirement in 2005. (Full article...)
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  Raman in 1930

  
  Sir Chandrasekhara Venkata Raman (/ˈrɑːmən/; 7 November 1888 – 21 November 1970), known simply as C. V. Raman, 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 when light traverses a transparent material, the deflected light changes its wavelength. This phenomenon, a hitherto unknown type of scattering of light, which they called modified scattering was subsequently termed the Raman effect or Raman scattering. In 1930, Raman received the Nobel Prize in Physics for this discovery and was the first Asian and the first non-White to receive a Nobel Prize in any branch of science.
  
  Born to Tamil Brahmin parents, Raman was a precocious child, completing his secondary and higher secondary education from St Aloysius' Anglo-Indian High School at the age of 11 and 13, respectively. He topped the bachelor's degree examination of the University of Madras with honours in physics from Presidency College at age 16. His first research paper, on diffraction of light, was published in 1906 while he was still a graduate student. The next year he obtained a master's degree. He joined the Indian Finance Service in Calcutta as Assistant Accountant General at age 19. There he became acquainted with the Indian Association for the Cultivation of Science (IACS), the first research institute in India, which allowed him to carry out independent research and where he made his major contributions in acoustics and optics. (Full article...)
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  Amedeo Avogadro, the constant's namesake

  
  The Avogadro constant, commonly denoted N_A or L, is an SI defining constant with an exact value of 6.02214076×10²³ mol⁻¹ (reciprocal moles). It is this defined number of constituent particles (usually molecules, atoms, ions, or ion pairs—in general, entities) per mole (SI unit) and used as a normalization factor in relating the amount of substance, n(X), in a sample of a substance X to the corresponding number of entities, N(X): n(X) = N(X)(1/N_A), an aggregate of N(X) reciprocal Avogadro constants. By setting N(X) = 1, a reciprocal Avogadro constant is seen to be equal to one entity, which means that n(X) is more easily interpreted as an aggregate of N(X) entities. In the SI dimensional analysis of measurement units, the dimension of the Avogadro constant is the reciprocal of amount of substance, denoted N⁻¹. The Avogadro number, sometimes denoted N₀, is the numeric value of the Avogadro constant (i.e., without a unit), namely the dimensionless number 6.02214076×10²³; the value chosen based on the number of atoms in 12 grams of carbon-12 in alignment with the historical definition of a mole. The constant is named after the Italian physicist and chemist Amedeo Avogadro (1776–1856).
  
  The Avogadro constant N_A is also the factor that converts the average mass ($m$) of one particle, in grams, to the molar mass ($M$) of the substance, in grams per mole (g/mol). That is, $M=m\cdot N_{A}$. (Full article...)
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  The Nobel Prize in Physics (Swedish: Nobelpriset i fysik) is an annual award given by the Royal Swedish Academy of Sciences for those who have made the most outstanding contributions to mankind in the field of physics. It is one of the five Nobel Prizes established by the will of Alfred Nobel in 1895 and awarded since 1901, the others being the Nobel Prize in Chemistry, Nobel Prize in Literature, Nobel Peace Prize, and Nobel Prize in Physiology or Medicine. Physics is traditionally the first award presented in the Nobel Prize ceremony.
  
  The prize consists of a medal along with a diploma and a certificate for the monetary award. The front side of the medal displays the same profile of Alfred Nobel depicted on the medals for Physics, Chemistry, and Literature. (Full article...)
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  A series of 5, 2, 1, 0.5 and 0.2 kilogram weights, made of cast iron

  
  The kilogram (also spelled kilogramme) is the base unit of mass in the International System of Units (SI), having the unit symbol kg. 'Kilogram' means 'one thousand grams' and is colloquially abbreviated to kilo.
  
  The kilogram is an SI base unit, defined ultimately in terms of three defining constants of the SI, namely a specific transition frequency of the caesium-133 atom, the speed of light, and the Planck constant. A properly equipped metrology laboratory can calibrate a mass measurement instrument such as a Kibble balance as a primary standard for the kilogram mass. (Full article...)
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  Geocentric celestial spheres; Peter Apian's Cosmographia (Antwerp, 1539)

  
  
  The celestial spheres, or celestial orbs, were the fundamental entities of the cosmological models developed by Plato, Eudoxus, Aristotle, Ptolemy, Copernicus, and others. In these celestial models, the apparent motions of the fixed stars and planets are accounted for by treating them as embedded in rotating spheres made of an aetherial, transparent fifth element (quintessence), like gems set in orbs. Since it was believed that the fixed stars did not change their positions relative to one another, it was argued that they must be on the surface of a single starry sphere.
  
  In modern thought, the orbits of the planets are viewed as the paths of those planets through mostly empty space. Ancient and medieval thinkers, however, considered the celestial orbs to be thick spheres of rarefied matter nested one within the other, each one in complete contact with the sphere above it and the sphere below. When scholars applied Ptolemy's epicycles, they presumed that each planetary sphere was exactly thick enough to accommodate them. By combining this nested sphere model with astronomical observations, scholars calculated what became generally accepted values at the time for the distances to the Sun: about 4 million miles (6.4 million kilometres), to the other planets, and to the edge of the universe: about 73 million miles (117 million kilometres). The nested sphere model's distances to the Sun and planets differ significantly from modern measurements of the distances, and the size of the universe is now known to be inconceivably large and continuously expanding. (Full article...)
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  Samuel King Allison (November 13, 1900 – September 15, 1965) was an American physicist, most notable for his role in the Manhattan Project, for which he was awarded the Medal for Merit. A professor who studied X-rays, he was director of the Metallurgical Laboratory from 1943 until 1944, and later worked at the Los Alamos Laboratory — where he "rode herd" on the final stages of the project as part of the "Cowpuncher Committee", and read the countdown for the detonation of the Trinity nuclear test. After the war, he returned to the University of Chicago to direct the Institute for Nuclear Studies and was involved in the "scientists' movement", lobbying for civilian control of nuclear weapons. (Full article...)
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  Electrical elastance is the reciprocal of capacitance. The SI unit of elastance is the inverse farad (F⁻¹). The concept is not widely used by electrical and electronic engineers, as the value of capacitors is typically specified in units of capacitance rather than inverse capacitance. However, elastance is used in theoretical work in network analysis and has some niche applications, particularly at microwave frequencies.
  
  The term elastance was coined by Oliver Heaviside through the analogy of a capacitor to a spring. The term is also used for analogous quantities in other energy domains. In the mechanical domain, it corresponds to stiffness, and it is the inverse of compliance in the fluid flow domain, especially in physiology. It is also the name of the generalized quantity in bond-graph analysis and other schemes that analyze systems across multiple domains. (Full article...)
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  A tau emerald (Hemicordulia tau) dragonfly has flight muscles attached directly to its wings.

  
  
  Insects are the only group of invertebrates that have evolved wings and flight. Insects first flew in the Carboniferous, some 300 to 350 million years ago, making them the first animals to evolve flight. Wings may have evolved from appendages on the sides of existing limbs, which already had nerves, joints, and muscles used for other purposes. These may initially have been used for sailing on water, or to slow the rate of descent when gliding.
  
  Two insect groups, the dragonflies and the mayflies, have flight muscles attached directly to the wings. In other winged insects, flight muscles attach to the thorax, which make it oscillate in order to induce the wings to beat. Of these insects, some (flies and some beetles) achieve very high wingbeat frequencies through the evolution of an "asynchronous" nervous system, in which the thorax oscillates faster than the rate of nerve impulses. (Full article...)
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  The SI system after the 2019 definition: Base units as defined in terms of physical constants and other base units. Here, $a\rightarrow b$ means $a$ is used in the definition of $b$.

  
  In 2019, four of the seven SI base units specified in the International System of Quantities were redefined in terms of natural physical constants, rather than human artefacts such as the standard kilogram. Effective 20 May 2019, the 144th anniversary of the Metre Convention, the kilogram, ampere, kelvin, and mole are now defined by setting exact numerical values, when expressed in SI units, for the Planck constant (h), the elementary electric charge (e), the Boltzmann constant (k_B), and the Avogadro constant (N_A), respectively. The second, metre, and candela had previously been redefined using physical constants. The four new definitions aimed to improve the SI without changing the value of any units, ensuring continuity with existing measurements. In November 2018, the 26th General Conference on Weights and Measures (CGPM) unanimously approved these changes, which the International Committee for Weights and Measures (CIPM) had proposed earlier that year after determining that previously agreed conditions for the change had been met. These conditions were satisfied by a series of experiments that measured the constants to high accuracy relative to the old SI definitions, and were the culmination of decades of research.
  
  The previous major change of the metric system occurred in 1960 when the International System of Units (SI) was formally published. At this time the metre was redefined: the definition was changed from the prototype of the metre to a certain number of wavelengths of a spectral line of a krypton-86 radiation, making it derivable from universal natural phenomena. The kilogram remained defined by a physical prototype, leaving it the only artefact upon which the SI unit definitions depend. At this time the SI, as a coherent system, was constructed around seven base units, powers of which were used to construct all other units. With the 2019 redefinition, the SI is constructed around seven defining constants, allowing all units to be constructed directly from these constants. The designation of base units is retained but is no longer essential to define the SI units. (Full article...)
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  In a nuclear weapon, a tamper is an optional layer of dense material surrounding the fissile material. It is used in nuclear weapon design to reduce the critical mass and to delay the expansion of the reacting material through its inertia, which delays the thermal expansion of the fissioning fuel mass, keeping it supercritical longer. Often the same layer serves both as tamper and as neutron reflector. The weapon disintegrates as the reaction proceeds, and this stops the reaction, so the use of a tamper makes for a longer-lasting, more energetic and more efficient explosion. The yield can be further enhanced using a fissionable tamper.
  
  The first nuclear weapons used heavy natural uranium or tungsten carbide tampers, but a heavy tamper necessitates a larger high-explosive implosion system and makes the entire device larger and heavier. The primary stage of a modern thermonuclear weapon may instead use a lightweight beryllium reflector, which is also transparent to X-rays when ionized, allowing the primary's energy output to escape quickly to be used in compressing the secondary stage. More exotic tamper materials such as gold are used for special purposes like emitting large amounts of X-rays or altering the amount of nuclear fallout. (Full article...)
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  Units in everyday use by country as of 2019

  
  The history of the metric system began during the Age of Enlightenment with measures of length and weight derived from nature, along with their decimal multiples and fractions. The system became the standard of France and Europe within half a century. Other measures with unity ratios were added, and the system went on to be adopted across the world.
  
  The first practical realisation of the metric system came in 1799, during the French Revolution, after the existing system of measures had become impractical for trade, and was replaced by a decimal system based on the kilogram and the metre. The basic units were taken from the natural world. The unit of length, the metre, was based on the dimensions of the Earth, and the unit of mass, the kilogram, was based on the mass of a volume of water of one litre (a cubic decimetre). Reference copies for both units were manufactured in platinum and remained the standards of measure for the next 90 years. After a period of reversion to the mesures usuelles due to unpopularity of the metric system, the metrication of France and much of Europe was complete by the 1850s. (Full article...)
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  Alvin Cushman Graves (November 4, 1909 – July 28, 1965) was an American nuclear physicist who served at the Manhattan Project's Metallurgical Laboratory and the Los Alamos Laboratory during World War II. After the war, he became the head of the J (Test) Division at Los Alamos and was director or assistant director of numerous nuclear weapons tests during the 1940s and 1950s. Graves was severely injured in the 1946 laboratory criticality accident in Los Alamos that killed Louis Slotin, but recovered. (Full article...)
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  Ernest Orlando Lawrence (August 8, 1901 – August 27, 1958) was an American nuclear physicist and laureate of the Nobel Prize in Physics in 1939 for his invention of the cyclotron. He is known for his work on uranium-isotope separation for the Manhattan Project, as well as for founding the Lawrence Berkeley National Laboratory and the Lawrence Livermore National Laboratory.
  
  A graduate of the University of South Dakota and University of Minnesota, Lawrence obtained a PhD in physics at Yale in 1925. In 1928, he was hired as an associate professor of physics at the University of California, Berkeley, becoming the youngest full professor there two years later. In its library one evening, Lawrence was intrigued by a diagram of an accelerator that produced high-energy particles. He contemplated how it could be made compact, and came up with an idea for a circular accelerating chamber between the poles of an electromagnet. The result was the first cyclotron. (Full article...)
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  Edward Condon at NIST (c. 1945-1951)

  
  Edward Uhler Condon (March 2, 1902 – March 26, 1974) was an American nuclear physicist, a pioneer in quantum mechanics, and a participant during World War II in the development of radar and, very briefly, of nuclear weapons as part of the Manhattan Project. The Franck–Condon principle and the Slater–Condon rules are co-named after him.
  
  He was the director of the National Bureau of Standards (now NIST) from 1945 to 1951. In 1946, Condon was president of the American Physical Society, and in 1953 was president of the American Association for the Advancement of Science. (Full article...)

December anniversaries

• 1610 – Galileo Galilei observes phases of Venus.
• 1900 - The peer reviewed journal "Nature" reports on Duddell's "Singing Arc" American Physical Society.
• 1942 - First self-sustained nuclear chain reaction at the University of Chicago under the supervision of Enrico Fermi. American Physical Society
• 1968 – Apollo 8 Launched
• 1995 – Hubble Deep Field images taken.

Births

• 1852 - Henri Becquerel
• 1900 - George Eugene Uhlenbeck
• 25 December, 1642 - Isaac Newton
• 5 December, 1901 - Werner Heisenberg
• 18 December, 1856 - J. J. Thomson

General images

The following are images from various physics-related articles on Wikipedia.

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  Ibn al-Haytham (c. 965–1040). (from History of physics)
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  Classical physics (Rayleigh–Jeans law, black line) failed to explain black-body radiation – the so-called ultraviolet catastrophe. The quantum description (Planck's law, colored lines) is said to be modern physics. (from Modern physics)
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  Ludwig Boltzmann
  (1844–1906) (from History of physics)
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  Sir Isaac Newton
  (1642–1727) (from History of physics)
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  Michael Faraday
  (1791–1867) (from History of physics)
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  A replica of the first point-contact transistor in Bell labs (from Condensed matter physics)
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  The first Bose–Einstein condensate observed in a gas of ultracold rubidium atoms. The blue and white areas represent higher density. (from Condensed matter physics)
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  Johannes Kepler. (from History of physics)
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  Aristotle
  (384–322 BCE) (from History of physics)
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  Werner Heisenberg
  (1901–1976) (from History of physics)
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  A magnet levitating above a high-temperature superconductor. Today some physicists are working to understand high-temperature superconductivity using the AdS/CFT correspondence. (from Condensed matter physics)
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  Christiaan Huygens
  (1629–1695) (from History of physics)
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  Albert Einstein (1879–1955), photographed here in around 1905 (from History of physics)
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  Einstein proposed that gravitation is a result of masses (or their equivalent energies) curving ("bending") the spacetime in which they exist, altering the paths they follow within it. (from History of physics)
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  A page from al-Khwārizmī's Algebra. (from History of physics)
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  Computer simulation of nanogears made of fullerene molecules. It is hoped that advances in nanoscience will lead to machines working on the molecular scale. (from Condensed matter physics)
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  Alessandro Volta
  (1745–1827) (from History of physics)
• 
  Daniel Bernoulli
  (1700–1782) (from History of physics)
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  Image of X-ray diffraction pattern from a protein crystal (from Condensed matter physics)
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  A composite montage comparing Jupiter (lefthand side) and its four Galilean moons (top to bottom: Io, Europa, Ganymede, Callisto) (from History of physics)
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  Galileo Galilei, early proponent of the modern scientific worldview and method
  (1564–1642) (from History of physics)
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  Classical physics is usually concerned with everyday conditions: speeds are much lower than the speed of light, sizes are much greater than that of atoms, yet very small in astronomical terms. Modern physics, however, is concerned with high velocities, small distances, and very large energies. (from Modern physics)
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  Marie Skłodowska-Curie
  (1867–1934) She was awarded two Nobel prizes, Physics (1903) and Chemistry (1911) (from History of physics)
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  A Newton's cradle, named after physicist Isaac Newton (from History of physics)
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  The ancient Greek mathematician Archimedes, developer of ideas regarding fluid mechanics and buoyancy. (from History of physics)
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  J. J. Thomson (1856–1940) discovered the electron and isotopy and also invented the mass spectrometer. He was awarded the Nobel Prize in Physics in 1906. (from History of physics)
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  Heike Kamerlingh Onnes and Johannes van der Waals with the helium liquefactor at Leiden in 1908 (from Condensed matter physics)
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  Richard Feynman's Los Alamos ID badge (from History of physics)
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  The Hindu-Arabic numeral system. The inscriptions on the edicts of Ashoka (3rd century BCE) display this number system being used by the Imperial Mauryas. (from History of physics)
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  Max Planck
  (1858–1947) (from History of physics)
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  René Descartes
  (1596–1650) (from History of physics)
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  One possible signature of a Higgs boson from a simulated proton–proton collision. It decays almost immediately into two jets of hadrons and two electrons, visible as lines. (from History of physics)
• 
  The quantum Hall effect: Components of the Hall resistivity as a function of the external magnetic field (from Condensed matter physics)
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  Chien-Shiung Wu worked on parity violation in 1956 and announced her results in January 1957. (from History of physics)
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  William Thomson (Lord Kelvin)
  (1824–1907) (from History of physics)
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  Star maps by the 11th-century Chinese polymath Su Song are the oldest known woodblock-printed star maps to have survived to the present day. This example, dated 1092, employs the cylindrical equirectangular projection. (from History of physics)
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  James Clerk Maxwell
  (1831–1879) (from History of physics)
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  Gottfried Leibniz
  (1646–1716) (from History of physics)
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  The German/Polish astronomer Nicolaus Copernicus (1473–1543) is remembered for his development of a heliocentric model of the Solar System. (from History of physics)
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  A Feynman diagram representing (left to right) the production of a photon (blue sine wave) from the annihilation of an electron and its complementary antiparticle, the positron. The photon becomes a quark–antiquark pair and a gluon (green spiral) is released. (from History of physics)
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  An artist's rendition of Kepler-62f, a potentially habitable exoplanet discovered using data transmitted by the Kepler space telescope, named after Kepler. (from History of physics)
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  The Standard Model (from History of physics)

Categories

Category puzzle

Fundamentals: Concepts in physics | Constants | Physical quantities | Units of measure | Mass | Length | Time | Space | Energy | Matter | Force | Gravity | Electricity | Magnetism | Waves

Basic physics: Mechanics | Electromagnetism | Statistical mechanics | Thermodynamics | Quantum mechanics | Theory of relativity | Optics | Acoustics

Specific fields: Acoustics | Astrophysics | Atomic physics | Molecular physics | Optical physics | Computational physics | Condensed matter physics | Nuclear physics | Particle physics | Plasma physics

Tools: Detectors | Interferometry | Measurement | Radiometry | Spectroscopy | Transducers

Background: Physicists | History of physics | Philosophy of physics | Physics education | Physics journals | Physics organizations

Other: Physics in fiction | Physics lists | Physics software | Physics stubs

Physics topics

Classical physics traditionally includes the fields of mechanics, optics, electricity, magnetism, acoustics and thermodynamics. The term Modern physics is normally used for fields which rely heavily on quantum theory, including quantum mechanics, atomic physics, nuclear physics, particle physics and condensed matter physics. General and special relativity are usually considered to be part of modern physics as well.

Fundamental Concepts	Classical Physics	Modern Physics	Cross Discipline Topics
Continuum	Solid Mechanics	Fluid Mechanics	Geophysics
Motion	Classical Mechanics	Analytical mechanics	Mathematical Physics
Kinetics	Kinematics	Kinematic chain	Robotics
Matter	Classical states	Modern states	Nanotechnology
Energy	Chemical Physics	Plasma Physics	Materials Science
Cold	Cryophysics	Cryogenics	Superconductivity
Heat	Heat transfer	Transport Phenomena	Combustion
Entropy	Thermodynamics	Statistical mechanics	Phase transitions
Particle	Particulates	Particle physics	Particle accelerator
Antiparticle	Antimatter	Annihilation physics	Gamma ray
Waves	Oscillation	Quantum oscillation	Vibration
Gravity	Gravitation	Gravitational wave	Celestial mechanics
Vacuum	Pressure physics	Vacuum state physics	Quantum fluctuation
Random	Statistics	Stochastic process	Brownian motion
Spacetime	Special Relativity	General Relativity	Black holes
Quantum	Quantum mechanics	Quantum field theory	Quantum computing
Radiation	Radioactivity	Radioactive decay	Cosmic ray
Light	Optics	Quantum optics	Photonics
Electrons	Solid State	Condensed Matter	Symmetry breaking
Electricity	Electrical circuit	Electronics	Integrated circuit
Electromagnetism	Electrodynamics	Quantum Electrodynamics	Chemical Bonds
Strong interaction	Nuclear Physics	Quantum Chromodynamics	Quark model
Weak interaction	Atomic Physics	Electroweak theory	Radioactivity
Standard Model	Fundamental interaction	Grand Unified Theory	Higgs boson
Information	Information science	Quantum information	Holographic principle
Life	Biophysics	Quantum Biology	Astrobiology
Conscience	Neurophysics	Quantum mind	Quantum brain dynamics
Cosmos	Astrophysics	Cosmology	Observable universe
Cosmogony	Big Bang	Mathematical universe	Multiverse
Chaos	Chaos theory	Quantum chaos	Perturbation theory
Complexity	Dynamical system	Complex system	Emergence
Quantization	Canonical quantization	Loop quantum gravity	Spin foam
Unification	Quantum gravity	String theory	Theory of Everything

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