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.

---

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 -

Mock mirage of the setting sun

• ... the mirage of astronomical objects is an optical phenomenon, which produces distorted or multiple images of astronomical objects such as the Sun, the Moon, the planets, bright stars and very bright comets

• ... that your watch would run slower when orbiting a black hole than it would on Earth?

• ... that homing pigeons wouldn't be able to navigate on Mercury because the planet has no magnetic field or atmosphere?

Selected image -

Magnetosphere of Jupiter

The magnetosphere of Jupiter is the cavity created in the solar wind by the planet's magnetic field. Extending up to seven million kilometers in the Sun's direction and almost to the orbit of Saturn in the opposite direction, Jupiter's magnetosphere is the largest and most powerful of any planetary magnetosphere in the Solar System, and by volume the largest known continuous structure in the Solar System after the heliosphere. Wider and flatter than the Earth's magnetosphere, Jupiter's is stronger by an order of magnitude, while its magnetic moment is roughly 18,000 times larger. The existence of Jupiter's magnetic field was first inferred from observations of radio emissions at the end of the 1950s and was directly observed by the Pioneer 10 spacecraft in 1973.

The main driver of Jupiter's magnetosphere is the planet's rotation. In this respect Jupiter is similar to a device called a Unipolar generator. When Jupiter rotates, its ionosphere moves relatively to the dipole magnetic field of the planet. Because the dipole magnetic moment points in the direction of the rotation, the Lorentz force, which appears as a result of this motion, drives negatively charged electrons to the poles, while positively charged ions are pushed towards the equator. As a result, the poles become negatively charged and the regions closer to the equator become positively charged. Since the magnetosphere of Jupiter is filled with highly conductive plasma, the electrical circuit is closed through it.

The Io plasma torus is in yellow. Jupiter's volcanically active moon Io is a strong source of plasma in its own right, and loads Jupiter's magnetosphere with as much as 1,000 kg of new material every second. Strong volcanic eruptions on Io emit huge amounts of sulfur dioxide, a major part of which is dissociated into atoms and ionized by the solar ultraviolet radiation, producing ions of sulfur and oxygen: S+, O+, S2+ and O2+. These ions escape from the satellite's atmosphere and form the Io plasma torusIo's interaction with Jupiter's magnetosphere. As a result of several processes, the plasma slowly leaks away from Jupiter

Bow shock

Related portals

Good articles -

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

---

• 
  Katharine "Kay" Way (February 20, 1902 – December 9, 1995) was an American physicist best known for her work on the Nuclear Data Project. During World War II, she worked for the Manhattan Project at the Metallurgical Laboratory in Chicago. She became an adjunct professor at Duke University in 1968. (Full article...)
• 
  
  

  

  Margaret Eliza Maltby, circa 1908

  
  Margaret Eliza Maltby (December 10, 1860 – May 3, 1944) was an American physicist notable for her measurement of high electrolytic resistances and the conductivity of very dilute solutions. Maltby was the first woman to earn a Bachelor of Science degree from the Massachusetts Institute of Technology, and the first woman to earn a Ph.D. in physics from any German university.
  
  She taught for over 30 years at Barnard College where she introduced one of the first courses on the physics of music. Maltby was active in the American Association of University Women where she was instrumental in helping female academics receive fellowships to study and conduct research, at a time when it was uncommon for women to be eligible for such fellowships. (Full article...)
• 

  

  The Type Ib supernova SN 2008D in galaxy NGC 2770, shown in X-ray (left) and visible light (right), at the corresponding positions of the images. (NASA image.)

  
  
  Type Ib and Type Ic supernovae are categories of supernovae that are caused by the stellar core collapse of massive stars. These stars have shed or been stripped of their outer envelope of hydrogen, and, when compared to the spectrum of Type Ia supernovae, they lack the absorption line of silicon. Compared to Type Ib, Type Ic supernovae are hypothesized to have lost more of their initial envelope, including most of their helium. The two types are usually referred to as stripped core-collapse supernovae. (Full article...)
• 

  

  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...)
• 

  

  
  Noctilucent clouds (NLCs), or night shining clouds, are tenuous cloud-like phenomena in the upper atmosphere of Earth. When viewed from space, they are called polar mesospheric clouds (PMCs), detectable as a diffuse scattering layer of water ice crystals near the summer polar mesopause. They consist of ice crystals and from the ground are only visible during astronomical twilight. Noctilucent roughly means "night shining" in Latin. They are most often observed during the summer months from latitudes between ±50° and ±70°. Too faint to be seen in daylight, they are visible only when the observer and the lower layers of the atmosphere are in Earth's shadow, but while these very high clouds are still in sunlight. Recent studies suggest that increased atmospheric methane emissions produce additional water vapor through chemical reactions once the methane molecules reach the mesosphere – creating, or reinforcing existing, noctilucent clouds.
  
  They are the highest clouds in Earth's atmosphere, located in the mesosphere at altitudes of around 76 to 85 km (249,000 to 279,000 ft). (Full article...)
• 

  

  
  Hans Albrecht Bethe (/ˈbɛθə/; German: [ˈhans ˈbeːtə] ; July 2, 1906 – March 6, 2005) was a German-American physicist who made major contributions to nuclear physics, astrophysics, quantum electrodynamics and solid-state physics, and received the Nobel Prize in Physics in 1967 for his work on the theory of stellar nucleosynthesis. For most of his career, Bethe was a professor at Cornell University.
  
  During World War II, he was head of the Theoretical Division at the secret Los Alamos laboratory that developed the first atomic bombs. There he played a key role in calculating the critical mass of the weapons and developing the theory behind the implosion method used in both the Trinity test and the "Fat Man" weapon dropped on Nagasaki in August 1945. (Full article...)
• 
  
  

  

  Forces can be described as a push or pull on an object. They can be due to phenomena such as gravity, magnetism, or anything that might cause a mass to accelerate.

  
  A force is an influence that can cause an object to change its velocity unless counterbalanced by other forces. The concept of force makes the everyday notion of pushing or pulling mathematically precise. Because the magnitude and direction of a force are both important, force is a vector quantity. The SI unit of force is the newton (N), and force is often represented by the symbol F.
  
  Force plays an important role in classical mechanics. The concept of force is central to all three of Newton's laws of motion. Types of forces often encountered in classical mechanics include elastic, frictional, contact or "normal" forces, and gravitational. The rotational version of force is torque, which produces changes in the rotational speed of an object. In an extended body, each part often applies forces on the adjacent parts; the distribution of such forces through the body is the internal mechanical stress. In equilibrium these stresses cause no acceleration of the body as the forces balance one another. If these are not in equilibrium they can cause deformation of solid materials, or flow in fluids. (Full article...)
• 

  

  
  John Harmen "Jack" Marburger III (February 8, 1941 – July 28, 2011) was an American physicist who directed the Office of Science and Technology Policy in the administration of President George W. Bush, serving as the Science Advisor to the President. His tenure was marred by controversy regarding his defense of the administration against allegations from over two dozen Nobel Laureates, amongst others, that scientific evidence was being suppressed or ignored in policy decisions, including those relating to stem cell research and global warming. However, he has also been credited with keeping the political effects of the September 11 attacks from harming science research—by ensuring that tighter visa controls did not hinder the movement of those engaged in scientific research—and with increasing awareness of the relationship between science and government. He also served as the President of Stony Brook University from 1980 until 1994, and director of Brookhaven National Laboratory from 1998 until 2001. (Full article...)
• 

  

  
  Charles Allen Thomas (February 15, 1900 – March 29, 1982) was a noted American chemist and businessman, and an important figure in the Manhattan Project. He held over 100 patents.
  
  A graduate of Transylvania College and Massachusetts Institute of Technology, Thomas worked as a research chemist at General Motors as part of a team researching antiknock agents. This led to the development of tetraethyllead, which was widely used in motor fuels for many decades until its toxicity led to its prohibition. In 1926, he and Carroll A. "Ted" Hochwalt co-founded Thomas & Hochwalt Laboratories in Dayton, Ohio, with Thomas as president of the company. It was acquired by Monsanto in 1936, and Thomas would spend the rest of his career with Monsanto, rising to become its president in 1950, and chairman of the board from 1960 to 1965. He researched the chemistry of hydrocarbons and polymers, and developed the proton theory of aluminium chloride, which helped explain a variety of chemical reactions, publishing a book on the subject in 1941. (Full article...)
• 
  
  

  

  Birch, c. 1970

  
  Albert Francis Birch (August 22, 1903 – January 30, 1992) was an American geophysicist. He is considered one of the founders of solid Earth geophysics. He is also known for his part in the atomic bombings of Hiroshima and Nagasaki.
  
  During World War II, Birch participated in the Manhattan Project, working on the design and development of the gun-type nuclear weapon known as Little Boy. He oversaw its manufacture, and went to Tinian to supervise its assembly and loading into Enola Gay, the Boeing B-29 Superfortress tasked with dropping the bomb. (Full article...)
• 
  Tropical cyclones are ranked on one of five tropical cyclone intensity scales, according to their maximum sustained winds and which tropical cyclone basins they are located in. Only a few classifications are used officially by the meteorological agencies monitoring the tropical cyclones, but other scales also exist, such as accumulated cyclone energy, the Power Dissipation Index, the Integrated Kinetic Energy Index, and the Hurricane Severity Index.
  
  Tropical cyclones that develop in the Northern Hemisphere are classified by the warning centres on one of three intensity scales. Tropical cyclones or subtropical cyclones that exist within the North Atlantic Ocean or the North-eastern Pacific Ocean are classified as either tropical depressions or tropical storms. Should a system intensify further and become a hurricane, then it will be classified on the Saffir–Simpson hurricane wind scale, and is based on the estimated maximum sustained winds over a 1-minute period. In the Western Pacific, the ESCAP/WMO Typhoon Committee uses four separate classifications for tropical cyclones that exist within the basin, which are based on the estimated maximum sustained winds over a 10-minute period. (Full article...)
• 
  
  

  

  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...)
• 

  

  The expanding remnant of SN 1987A, a peculiar Type II supernova in the Large Magellanic Cloud. NASA image.

  
  A Type II supernova or SNII (plural: supernovae) results from the rapid collapse and violent explosion of a massive star. A star must have at least eight times, but no more than 40 to 50 times, the mass of the Sun (M_☉) to undergo this type of explosion. Type II supernovae are distinguished from other types of supernovae by the presence of hydrogen in their spectra. They are usually observed in the spiral arms of galaxies and in H II regions, but not in elliptical galaxies; those are generally composed of older, low-mass stars, with few of the young, very massive stars necessary to cause a supernova.
  
  Stars generate energy by the nuclear fusion of elements. Unlike the Sun, massive stars possess the mass needed to fuse elements that have an atomic mass greater than hydrogen and helium, albeit at increasingly higher temperatures and pressures, causing correspondingly shorter stellar life spans. The degeneracy pressure of electrons and the energy generated by these fusion reactions are sufficient to counter the force of gravity and prevent the star from collapsing, maintaining stellar equilibrium. The star fuses increasingly higher mass elements, starting with hydrogen and then helium, progressing up through the periodic table until a core of iron and nickel is produced. Fusion of iron or nickel produces no net energy output, so no further fusion can take place, leaving the nickel–iron core inert. Due to the lack of energy output creating outward thermal pressure, the core contracts due to gravity until the overlying weight of the star can be supported largely by electron degeneracy pressure. (Full article...)
• 
  
  

  

  Wheeler in 1985

  
  John Archibald Wheeler (July 9, 1911 – April 13, 2008) was an American theoretical physicist. He was largely responsible for reviving interest in general relativity in the United States after World War II. Wheeler also worked with Niels Bohr to explain the basic principles of nuclear fission. Together with Gregory Breit, Wheeler developed the concept of the Breit–Wheeler process. He is best known for popularizing the term "black hole" for objects with gravitational collapse already predicted during the early 20th century, for inventing the terms "quantum foam", "neutron moderator", "wormhole" and "it from bit", and for hypothesizing the "one-electron universe". Stephen Hawking called Wheeler the "hero of the black hole story".
  
  At 21, Wheeler earned his doctorate at Johns Hopkins University under the supervision of Karl Herzfeld. He studied under Breit and Bohr on a National Research Council fellowship. In 1939 he collaborated with Bohr on a series of papers using the liquid drop model to explain the mechanism of fission. During World War II, he worked with the Manhattan Project's Metallurgical Laboratory in Chicago, where he helped design nuclear reactors, and then at the Hanford Site in Richland, Washington, where he helped DuPont build them. He returned to Princeton after the war but returned to government service to help design and build the hydrogen bomb in the early 1950s. He and Edward Teller were the main civilian proponents of thermonuclear weapons. (Full article...)
• 
  
  

  

  Einstein in 1921

  
  Albert Einstein (/ˈaɪnstaɪn/, EYEN-styne; German: [ˈalbɛʁt ˈʔaɪnʃtaɪn] ; 14 March 1879 – 18 April 1955) was a German-born theoretical physicist who is best known for developing the theory of relativity. Einstein also made important contributions to quantum mechanics. His mass–energy equivalence formula E = mc², which arises from special relativity, has been called "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.
  
  Born in the German Empire, Einstein moved to Switzerland in 1895, forsaking his German citizenship (as a subject of the Kingdom of Württemberg) the following year. In 1897, at the age of seventeen he enrolled in the mathematics and physics teaching diploma program at the Swiss Federal Polytechnic School in Zurich, graduating in 1900. In 1901, he acquired Swiss citizenship. In 1903, he secured a permanent position at the Swiss Patent Office in Bern. In 1905, he submitted a successful PhD dissertation to the University of Zurich. In 1914, he moved to Berlin to join the Prussian Academy of Sciences and the Humboldt University of Berlin, becoming director of the Kaiser Wilhelm Institute for Physics in 1917; he also became a German citizen again, this time as a subject of the Kingdom of Prussia. In 1933, while Einstein was visiting the United States, Adolf Hitler came to power in Germany. Horrified by the Nazi persecution of his fellow Jews, he decided to remain in the US, and was granted American citizenship in 1940. On the eve of World War II, he endorsed a letter to President Franklin D. Roosevelt alerting him to the potential German nuclear weapons program and recommended that the US begin similar research. He viewed the idea of nuclear weapons with great dismay. (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.

• 
  Heike Kamerlingh Onnes and Johannes van der Waals with the helium liquefactor at Leiden in 1908 (from Condensed matter physics)
• 
  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)
• 
  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)
• 
  Gottfried Leibniz
  (1646–1716) (from History of physics)
• 
  Max Planck
  (1858–1947) (from History of physics)
• 
  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)
• 
  William Thomson (Lord Kelvin)
  (1824–1907) (from History of physics)
• 
  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)
• 
  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)
• 
  Image of X-ray diffraction pattern from a protein crystal (from Condensed matter physics)
• 
  Richard Feynman's Los Alamos ID badge (from History of physics)
• 
  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)
• 
  Aristotle
  (384–322 BCE) (from History of physics)
• 
  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)
• 
  Albert Einstein (1879–1955), photographed here in around 1905 (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)
• 
  Galileo Galilei, early proponent of the modern scientific worldview and method
  (1564–1642) (from History of physics)
• 
  James Clerk Maxwell
  (1831–1879) (from History of physics)
• 
  René Descartes
  (1596–1650) (from History of physics)
• 
  Werner Heisenberg
  (1901–1976) (from History of physics)
• 
  A composite montage comparing Jupiter (lefthand side) and its four Galilean moons (top to bottom: Io, Europa, Ganymede, Callisto) (from History of physics)
• 
  The Standard Model (from History of physics)
• 
  The Polish astronomer Nicolaus Copernicus (1473–1543) is remembered for his development of a heliocentric model of the Solar System. (from History of physics)
• 
  A replica of the first point-contact transistor in Bell labs (from Condensed matter physics)
• 
  Rudolf Clausius
  (1822–1888) (from History of physics)
• 
  Chien-Shiung Wu worked on parity violation in 1956 and announced her results in January 1957. (from History of physics)
• 
  Sir Isaac Newton
  (1642–1727) (from History of physics)
• 
  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)
• 
  Christiaan Huygens
  (1629–1695) (from History of physics)
• 
  Johannes Kepler. (from History of physics)
• 
  A page from al-Khwārizmī's Algebra. (from History of physics)
• 
  Ludwig Boltzmann
  (1844–1906) (from History of physics)
• 
  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)
• 
  Daniel Bernoulli
  (1700–1782) (from History of physics)
• 
  Alessandro Volta
  (1745–1827) (from History of physics)
• 
  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)
• 
  Ibn al-Haytham (c. 965–1040). (from History of physics)
• 
  A Newton's cradle, named after physicist Isaac Newton (from History of physics)
• 
  Michael Faraday
  (1791–1867) (from History of physics)
• 
  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)
• 
  Marie Skłodowska-Curie
  (1867–1934) She was awarded two Nobel prizes, Physics (1903) and Chemistry (1911) (from History of physics)
• 
  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)
• 
  The ancient Greek mathematician Archimedes, developer of ideas regarding fluid mechanics and buoyancy. (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

More recognized content

Associated Wikimedia

The following Wikimedia Foundation sister projects provide more on this subject:

• 

  Commons
  Free media repository

• 

  Wikibooks
  Free textbooks and manuals

• 

  Wikidata
  Free knowledge base

• 

  Wikinews
  Free-content news

• 

  Wikiquote
  Collection of quotations

• 

  Wikisource
  Free-content library

• 

  Wikiversity
  Free learning tools

• 

  Wikivoyage
  Free travel guide

• 

  Wiktionary
  Dictionary and thesaurus

Sources

Portals on Wikipedia

Discover Wikipedia using portals

• 

  List of all portals

• 

  The arts portal

• 

  Biography portal

• 

  Current events portal

• 

  Geography portal

• 

  History portal

• 

  Mathematics portal

• 

  Science portal

• 

  Society portal

• 

  Technology portal

• 

  Random portal

• 

  WikiProject Portals