All articles starting with W

Wigner distribution function

The Wigner distribution function, known in signal processing as the Wigner–Ville distribution, is a bilinear transform representing a signal in time and frequency, introduced by Eugene Wigner in 1932.

Wigner effect

The Wigner effect, also called Wigner's disease, is damage in crystalline solids, chiefly graphite, when fast neutrons displace atoms and store energy in the lattice.

Wigner function

The Wigner function is a quasiprobability distribution of a quantum state over phase space; it yields correct position and momentum probabilities but can be negative, a signature of nonclassical states.

Wigner matrix

A Wigner matrix is a Hermitian or real symmetric random matrix with independent, zero-mean, constant-variance entries, introduced by Eugene Wigner in the 1950s to model heavy nuclei.

Wigner rotation

The Wigner rotation, also called the Thomas rotation, is the spatial rotation arising when two non-collinear Lorentz boosts compose; it underlies Thomas precession and lies in the particle's little group.

Wigner time delay in photoemission

Wigner time delay in photoemission is the attosecond-scale delay, or advance, in electron emission after a photon is absorbed, defined as the derivative of the electron's spectral phase.

Wigner-Eisenbud R-matrix theory

The Wigner-Eisenbud R-matrix theory, introduced by Eugene Wigner and Leonard Eisenbud in 1947, describes nuclear and atomic scattering by splitting configuration space into internal and external regions.

Wigner–Eckart theorem

The Wigner–Eckart theorem is a result of quantum mechanics stating that matrix elements of irreducible tensor operators factor into a Clebsch–Gordan coefficient and a single reduced matrix element.

Wigner–Mott transition

The Wigner–Mott transition is an interaction-driven metal–insulator transition, predicted near extended Coulomb repulsion V comparable to bandwidth W, where a generalized Wigner crystal melts into a metal.

Wigner–Weyl transform

The Wigner–Weyl transform is the reciprocal pair of mappings connecting quantum operators with classical phase-space functions: Weyl's forward map, and Wigner's 1932 inverse, which yields the Wigner function.

Wigner's friend

Wigner's friend, or Wigner's paradox, is a thought experiment proposed by Eugene Wigner in 1961 in which two observers assign incompatible quantum descriptions of the same measurement.

Wigner's theorem

Wigner's theorem, stated by Eugene Wigner in 1931, says every symmetry of the quantum state space preserving transition probabilities is implemented by a unitary or antiunitary operator.

Wigry Monastery

Wigry Monastery (Klasztor Kamedułów w Wigrach) is a former Camaldolese hermit monastery on a peninsula of Lake Wigry in northeastern Poland, founded by King Jan II Kazimierz Waza in 1667.

Wigwag (flag signals)

Wigwag is a military signaling system using a single flag or torch waved in coded motions, invented by Albert Myer in the 1850s and used by both sides in the Civil War.

Wigwam

A wigwam, also called a wickiup, is a domed dwelling built by Indigenous peoples of the northeastern North American woodlands from bent saplings covered with bark or mats.

Sep 24, 2026

Wihwado Retreat

The Wihwado Retreat (위화도 회군) was the 1388 event in which Yi Seong-gye turned his army back at Wihwa Island, marched on Kaesong, and deposed King U.

Wii

Wii: Nintendo home console released November 19, 2006, seventh generation, built around the motion-sensing Wii Remote. Sold 101.63 million units; Wii Sports 82 million; Wii Shop Channel closed January 30, 2019.

Wii Remote

Wii Remote (Wiimote), Nintendo's primary wireless controller for the Wii console, released 2006; three-axis accelerometer, infrared camera with Sensor Bar pointing, Bluetooth link, later gyroscope via Wii MotionPlus/Wii Remote Plus.

Wii Sports

Wii Sports is Nintendo's 2006 Wii launch game of five motion-controlled sports, bundled with consoles outside Japan; it sold 82.9 million units, the third best-selling game, and spawned Resort, Club, and Switch Sports.

Wii Sports Resort

Wii Sports Resort is a 2009 Nintendo sports game for the Wii, the sequel to Wii Sports, offering 12 activities on Wuhu Island and requiring the included Wii MotionPlus accessory.

Wii U

Wii U: Nintendo home console with touchscreen GamePad (Display Remote Controller), IBM Power CPU, AMD Radeon GPU, near-full Wii backward compatibility; about 12.6 million sold; eShop purchases ended March 2023 and online services ended April 8, 2024.

Oct 21, 2026

Wijan Ponlid

Wijan Ponlid (วิจารณ์•พลฤทธิ์), born 1976, Thai boxer; won flyweight gold at Sydney 2000, beating Bolat Zhumadilov 19-12; second Thai Olympic champion after Somluck Kamsing.

Wijayarajasa

Wijayarajasa, also recorded as Vijayarājasa, was a fourteenth-century Javanese prince who held the title Bhre Wengker and was an uncle, father-in-law, and political counterpart of King Hayam Wuruk.

Sep 19, 2026

Wijono Tanoko

Wijono Tanoko, born 1952 in Malang, East Java, is an Indonesian businessman who has led Avian Brands, Indonesia's largest decorative paints company, as President Director since 1996.

Wik Peoples v Queensland

Wik Peoples v Queensland [1996] HCA 40, the Wik decision, was a High Court of Australia native title case holding that pastoral leases do not necessarily extinguish native title, which can coexist with leasehold, pastoral rights prevailing on inconsistency, prompting the 1998 Native Title Act amendments.

Wiki

A wiki is a website whose pages users can edit directly in a web browser, with every change saved as a version that can be viewed and restored.

Wiki software

Wiki software, also called a wiki engine, is software that lets users create and edit website pages in a browser, saving every change as a revertible revision.

Wiki Workers United

Wiki Workers United is a global solidarity union of paid Wikimedia Foundation staff, organized through country branches, which won an NLRB election in September 2026.

Wikibooks

Wikibooks is a Wikimedia Foundation project, started in 2003, of free collaboratively written textbooks, annotated texts, guides, and manuals, dual licensed CC BY-SA 4.0 and GFDL, editable by anyone, distinct from Wikipedia, Wikisource, and Wikiversity.