All articles starting with W
11,426 articles
Weak interaction
The weak interaction, or weak force, is one of the four fundamental forces, changing quarks and leptons' flavor and causing beta decay via the W and Z bosons.
Weak isospin
Weak isospin is the quantum number and gauge charge of the SU(2)L symmetry of the electroweak Standard Model, acting on left-handed fermion doublets and fixing electric charges with hypercharge.
Weak localization
Weak localization is a quantum-mechanical correction to the conductivity of disordered metals and semiconductors: constructive interference between an electron's path and its time reverse enhances backscattering and lowers conductivity.
Weak measurement
A weak measurement is a quantum measurement coupled so gently to a meter that it barely disturbs the system, a protocol introduced by Aharonov, Albert, and Vaidman in 1988.
Weak mixing angle
The weak mixing angle, or Weinberg angle, is the electroweak parameter describing how photon and Z boson arise; its sine squared is a fundamental Standard Model constant.
Weak ordering
A weak ordering is a transitive and complete binary relation on a set, equivalent to a total preorder. It also refers to the weak Bruhat order on Coxeter groups.
Weak r-process
The weak r-process, also called the limited r-process or LEPP, is a neutron-capture nucleosynthesis process forming light r-process elements, thought to occur in neutrino-driven winds from core-collapse supernovae.
Weak scaling
Weak scaling, also called scaled speedup, is a parallel performance method that increases problem size and processor count together, formalized by Gustafson's law in 1988.
Weak solution
A weak solution satisfies a partial differential equation through integral identities against test functions rather than pointwise differentiation, also called a generalized or distributional solution.
Weak stability boundary
A weak stability boundary is a transition region where Earth, Moon, and Sun gravity nearly balance, letting a spacecraft be captured ballistically with little or no propellant.
Weak supervision
Weak supervision is a machine learning approach that trains models from cheap, noisy, or coarse labels instead of hand-labeled data, covering incomplete, inexact, and inaccurate supervision.
Weak topology
The weak topology on a Banach space X is the coarsest topology making every bounded linear functional in X continuous, introduced by von Neumann in 1929.
Weak value
A weak value is a quantum mechanics quantity, the result of a weak measurement conditioned on a later post-selected strong measurement, introduced by Aharonov, Albert, and Vaidman in 1988.
Weak value amplification
Weak value amplification is a quantum measurement technique that enlarges tiny detector signals by weak coupling and post-selection, introduced by Aharonov, Albert, and Vaidman in 1988.
Weak-form efficiency
Weak-form efficiency is the form of the efficient market hypothesis asserting that prices fully reflect past prices and trading volumes, ruling out prediction from price history alone.
Weak-to-strong generalization
Weak-to-strong generalization is an AI alignment phenomenon in which a strong model finetuned only on a weaker model's labels outperforms its weak supervisor, named by OpenAI in December 2023.
Weakest Link
Weakest Link (The Weakest Link) is a BBC quiz format created in 2000 by Fintan Coyle and Cathy Dunning: contestants build money chains, bank winnings, and vote off the weakest link. Hosted by Anne Robinson until 2012, revived on NBC with Jane Lynch in 2020, sold to 97 countries.
Weakest precondition
The weakest precondition WP(c, Q) is the weakest condition on a program's initial state that guarantees it ends in a state satisfying Q, introduced by Dijkstra in 1975.
Weakly compact cardinal
A weakly compact cardinal is a large cardinal that is inaccessible and has the tree property, equivalent to satisfying the partition relation κ → (κ)²₂.
Weakly interacting massive particle
A weakly interacting massive particle (WIMP), known as a WIMP, is a hypothetical neutral particle heavier than a proton proposed as a leading cold dark matter candidate.
Weakly interacting slim particles (WISPs)
Weakly interacting slim particles (WISPs), also called weakly interacting sub-eV particles, are hypothetical particles with sub-eV masses and extremely feeble couplings to matter, including the QCD axion and axion-like particles.
Weakly supervised learning
Weakly supervised learning trains machine learning models from incomplete, inexact, or inaccurate labels instead of costly fully annotated ground truth, covering detection, segmentation, and classification.
Weakly supervised object detection
Weakly supervised object detection (WSOD) trains models to classify and locate objects in images using only cheap image-level class labels instead of costly bounding-box annotations.
Wealdstone F.C.
Wealdstone F.C. (the Stones), an English non-league football club founded in 1899, playing at Grosvenor Vale in Ruislip in the fifth-tier Enterprise National League; FA Amateur Cup winners 1966 and FA Trophy and Conference double winners 1984-85, National League South champions 2020, FA Trophy runners-up 2026.
Wealth
Wealth, also called personal wealth, is the value of assets a person, household, or nation owns minus its debts, what economists call net worth, distinct from income.
Wealth and religion
Wealth and religion: the reciprocal link between economic conditions and religiosity. Wealthier countries score lower on prayer, attendance, and religion's importance (correlation about -0.80); income gains causally reduce attendance, while religious affiliation and belief shape wealth accumulation.
Wealth effect
The wealth effect is the change in consumer spending that follows a change in household net worth: rising asset prices lift spending, falling prices cut it.
Wealth inequality in the United States
Wealth inequality in the United States is the unequal distribution of household net worth; in 2022 the top 10% of families held 60% of all wealth.
Wealth management
Wealth management is a financial service combining investment management with planning services such as tax, estate, trust, and insurance advice, typically for clients with $250,000 or more.
Wealth of Donald Trump
The wealth of Donald Trump, also called the finances of Donald Trump, consists mainly of New York and Florida real estate, Trump Media stock, golf clubs, and licensing deals.