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Quantum microscopy allows microscopic properties of matter and quantum particles to be measured and imaged. Various types of microscopy use quantum principles. The first microscope to do so was the scanning tunneling microscope , which paved the way for development of the photoionization microscope and the quantum enta... | https://en.wikipedia.org/wiki/Quantum_microscopy |
The quantum mind or quantum consciousness is a group of hypotheses proposing that local physical laws and interactions from classical mechanics or connections between neurons alone cannot explain consciousness , [ 1 ] positing instead that quantum-mechanical phenomena, such as entanglement and superposition that cause ... | https://en.wikipedia.org/wiki/Quantum_mind |
Quantum natural language processing (QNLP) is the application of quantum computing to natural language processing (NLP). It computes word embeddings as parameterised quantum circuits that can solve NLP tasks faster than any classical computer. [ 1 ] [ 2 ] [ 3 ] It is inspired by categorical quantum mechanics and the Di... | https://en.wikipedia.org/wiki/Quantum_natural_language_processing |
Quantum non-equilibrium is a concept within stochastic formulations of the De Broglie–Bohm theory of quantum physics .
In quantum mechanics, the Born rule states that the probability density of finding a system in a given state, when measured, is proportional to the square of the amplitude of the system's wavefunction... | https://en.wikipedia.org/wiki/Quantum_non-equilibrium |
In quantum physics and chemistry , quantum numbers are quantities that characterize the possible states of the system.
To fully specify the state of the electron in a hydrogen atom, four quantum numbers are needed. The traditional set of quantum numbers includes the principal , azimuthal , magnetic , and spin quantum ... | https://en.wikipedia.org/wiki/Quantum_number |
In quantum mechanics , a quantum operation (also known as quantum dynamical map or quantum process ) is a mathematical formalism used to describe a broad class of transformations that a quantum mechanical system can undergo. This was first discussed as a general stochastic transformation for a density matrix by George ... | https://en.wikipedia.org/wiki/Quantum_operation |
In condensed matter physics , quantum oscillations describes a series of related experimental techniques used to map the Fermi surface of a metal in the presence of a strong magnetic field . [ 1 ] These techniques are based on the principle of Landau quantization of Fermions moving in a magnetic field. [ 2 ] For a gas ... | https://en.wikipedia.org/wiki/Quantum_oscillations |
Quantum paraelectricity [ 1 ] is a type of incipient ferroelectricity where the onset of ferroelectric order is suppressed by quantum fluctuations. [ 2 ] From the soft mode theory of ferroelectricity, [ 3 ] this occurs when a ferroelectric instability is stabilized by quantum fluctuations . In this case the soft-mode f... | https://en.wikipedia.org/wiki/Quantum_paraelectricity |
In physics , a quantum phase transition ( QPT ) is a phase transition between different quantum phases ( phases of matter at zero temperature ). Contrary to classical phase transitions, quantum phase transitions can only be accessed by varying a physical parameter—such as magnetic field or pressure—at absolute zero tem... | https://en.wikipedia.org/wiki/Quantum_phase_transition |
Quantum phases are quantum states of matter at zero temperature. Even at zero temperature a quantum-mechanical system has quantum fluctuations and therefore can still support phase transitions. As a physical parameter is varied, quantum fluctuations can drive a phase transition into a different phase of matter. An exam... | https://en.wikipedia.org/wiki/Quantum_phases |
Quantum photoelectrochemistry is the investigation of the quantum mechanical nature of photoelectrochemistry , the subfield of study within physical chemistry concerned with the interaction of light with electrochemical systems, typically through the application of quantum chemical calculations . [ 1 ] Quantum photoele... | https://en.wikipedia.org/wiki/Quantum_photoelectrochemistry |
A quantum point contact ( QPC ) is a narrow constriction between two wide electrically conducting regions, of a width comparable to the electronic wavelength (nano- to micrometer). [ 1 ]
The importance of QPC lies in the fact that they prove quantisation of ballistic conductance in mesoscopic systems. The conductance ... | https://en.wikipedia.org/wiki/Quantum_point_contact |
The quantum potential or quantum potentiality is a central concept of the de Broglie–Bohm formulation of quantum mechanics , introduced by David Bohm in 1952.
Initially presented under the name quantum-mechanical potential , subsequently quantum potential , it was later elaborated upon by Bohm and Basil Hiley in its i... | https://en.wikipedia.org/wiki/Quantum_potential |
In quantum mechanics , a quantum process is a somewhat ambiguous term which usually refers to the time evolution of an ( open ) quantum system. Under very general assumptions, a quantum process is described by the quantum operation formalism (also known as a quantum dynamical map ), which is a linear , trace-preservin... | https://en.wikipedia.org/wiki/Quantum_process |
Quantum pseudo-telepathy describes the use of quantum entanglement to eliminate the need for classical communications. [ 1 ] [ 2 ] A nonlocal game is said to display quantum pseudo-telepathy if players who can use entanglement can win it with certainty while players without it can not. The prefix pseudo refers to the f... | https://en.wikipedia.org/wiki/Quantum_pseudo-telepathy |
A quantum reference frame is a reference frame which is treated quantum theoretically. It, like any reference frame , is an abstract coordinate system which defines physical quantities, such as time , position, momentum , spin , and so on. Because it is treated within the formalism of quantum theory , it has some inter... | https://en.wikipedia.org/wiki/Quantum_reference_frame |
In quantum mechanics , the quantum revival [ 1 ] is a periodic recurrence of the quantum wave function from its original form during the time evolution either many times in space as the multiple scaled fractions
in the form of the initial wave function (fractional revival) or approximately or exactly to its original
f... | https://en.wikipedia.org/wiki/Quantum_revival |
In quantum mechanics , quantum scarring is a phenomenon where the eigenstates of a classically chaotic quantum system have enhanced probability density around the paths of unstable classical periodic orbits. [ 2 ] [ 3 ] The instability of the periodic orbit is a decisive point that differentiates quantum scars from the... | https://en.wikipedia.org/wiki/Quantum_scar |
Quantum simulators permit the study of a quantum system in a programmable fashion. In this instance, simulators are special purpose devices designed to provide insight about specific physics problems. [ 1 ] [ 2 ] [ 3 ] Quantum simulators may be contrasted with generally programmable "digital" quantum computers , which ... | https://en.wikipedia.org/wiki/Quantum_simulator |
Quantum singular value transformation is a framework for designing quantum algorithms . It encompasses a variety of quantum algorithms for problems that can be solved with linear algebra , including Hamiltonian simulation , search problems , and linear system solving . [ 1 ] [ 2 ] [ 3 ] It was introduced in 2018 by And... | https://en.wikipedia.org/wiki/Quantum_singular_value_transformation |
A quantum solvent is essentially a superfluid (aka a quantum liquid ) used to dissolve another chemical species . Any superfluid can theoretically act as a quantum solvent, but in practice the only viable superfluid medium that can currently be used is helium-4 , and it has been successfully accomplished in controlled ... | https://en.wikipedia.org/wiki/Quantum_solvent |
In quantum mechanics , a quantum speed limit ( QSL ) is a limitation on the minimum time for a quantum system to evolve between two distinguishable (orthogonal) states. [ 1 ] QSL theorems are closely related to time-energy uncertainty relations. In 1945, Leonid Mandelstam and Igor Tamm derived a time-energy uncertainty... | https://en.wikipedia.org/wiki/Quantum_speed_limit |
The quantum spin Hall state is a state of matter proposed to exist in special, two-dimensional semiconductors that have a quantized spin-Hall conductance and a vanishing charge-Hall conductance. The quantum spin Hall state of matter is the cousin of the integer quantum Hall state, and that does not require the applicat... | https://en.wikipedia.org/wiki/Quantum_spin_Hall_effect |
In condensed matter physics , a quantum spin liquid is a phase of matter that can be formed by interacting quantum spins in certain magnetic materials. Quantum spin liquids (QSL) are generally characterized by their long-range quantum entanglement , fractionalized excitations , and absence of ordinary magnetic order .... | https://en.wikipedia.org/wiki/Quantum_spin_liquid |
A spin model is a mathematical model used in physics primarily to explain magnetism . Spin models may either be classical or quantum mechanical in nature. Spin models have been studied in quantum field theory as examples of integrable models . Spin models are also used in quantum information theory and computability th... | https://en.wikipedia.org/wiki/Quantum_spin_model |
Quantum spin tunneling , or quantum tunneling of magnetization, is a physical phenomenon by which the quantum mechanical state that describes the collective magnetization of a nanomagnet is a linear superposition of two states with well defined and opposite magnetization. Classically, the magnetic anisotropy favo... | https://en.wikipedia.org/wiki/Quantum_spin_tunneling |
The term quantum state discrimination collectively refers to quantum-informatics techniques, with the help of which, by performing a small number of measurements on a physical system, its specific quantum state can be identified . And this is provided that the set of states in which the system can be is known in advanc... | https://en.wikipedia.org/wiki/Quantum_state_discrimination |
In quantum information theory , quantum state purification refers to the process of representing a mixed state as a pure quantum state of higher-dimensional Hilbert space . The purification allows the original mixed state to be recovered by taking the partial trace over the additional degrees of freedom. The purificati... | https://en.wikipedia.org/wiki/Quantum_state_purification |
In physics , a quantum state space is an abstract space in which different "positions" represent not literal locations, but rather quantum states of some physical system . It is the quantum analog of the phase space of classical mechanics .
In quantum mechanics a state space is a separable complex Hilbert space . The ... | https://en.wikipedia.org/wiki/Quantum_state_space |
In physics , in the area of quantum information theory and quantum computation , quantum steering is a special kind of nonlocal correlation, which is intermediate between Bell nonlocality and quantum entanglement . A state exhibiting Bell nonlocality must also exhibit quantum steering, a state exhibiting quantum steeri... | https://en.wikipedia.org/wiki/Quantum_steering |
A pump is an alternating current -driven device that generates a direct current (DC). In the simplest configuration a pump has two leads connected to two reservoirs. In such open geometry, the pump takes particles from one reservoir and emits them into the other. Accordingly, a current is produced even if the reservoir... | https://en.wikipedia.org/wiki/Quantum_stirring,_ratchets,_and_pumping |
Quantum superposition is a fundamental principle of quantum mechanics that states that linear combinations of solutions to the Schrödinger equation are also solutions of the Schrödinger equation. This follows from the fact that the Schrödinger equation is a linear differential equation in time and position. More precis... | https://en.wikipedia.org/wiki/Quantum_superposition |
In quantum computing , quantum supremacy or quantum advantage is the goal of demonstrating that a programmable quantum computer can solve a problem that no classical computer can solve in any feasible amount of time, irrespective of the usefulness of the problem. [ 1 ] [ 2 ] [ 3 ] The term was coined by John Preskill i... | https://en.wikipedia.org/wiki/Quantum_supremacy |
A quantum t-design is a probability distribution over either pure quantum states or unitary operators which can duplicate properties of the probability distribution over the Haar measure for polynomials of degree t or less. Specifically, the average of any polynomial function of degree t over the design is exactly the ... | https://en.wikipedia.org/wiki/Quantum_t-design |
Quantum teleportation is a technique for transferring quantum information from a sender at one location to a receiver some distance away. While teleportation is commonly portrayed in science fiction as a means to transfer physical objects from one location to the next, quantum teleportation only transfers quantum infor... | https://en.wikipedia.org/wiki/Quantum_teleportation |
Quantum thermodynamics [ 1 ] [ 2 ] is the study of the relations between two independent physical theories: thermodynamics and quantum mechanics . The two independent theories address the physical phenomena of light and matter.
In 1905, Albert Einstein argued that the requirement of consistency between thermodynamics a... | https://en.wikipedia.org/wiki/Quantum_thermodynamics |
Quantum tomography or quantum state tomography is the process by which a quantum state is reconstructed using measurements on an ensemble of identical quantum states. [ 1 ] The source of these states may be any device or system which prepares quantum states either consistently into quantum pure states or otherwise into... | https://en.wikipedia.org/wiki/Quantum_tomography |
Quantum topology is a branch of mathematics that connects quantum mechanics with low-dimensional topology .
Dirac notation provides a viewpoint of quantum mechanics which becomes amplified into a framework that can embrace the amplitudes associated with topological spaces and the related embedding of one space within ... | https://en.wikipedia.org/wiki/Quantum_topology |
In a quantum field theory , charge screening can restrict the value of the observable "renormalized" charge of a classical theory. If the only resulting value of the renormalized charge is zero, the theory is said to be "trivial" or noninteracting. Thus, surprisingly, a classical theory that appears to describe interac... | https://en.wikipedia.org/wiki/Quantum_triviality |
The quantum tunneling of water occurs when water molecules in nanochannels exhibit quantum tunneling behavior that smears out the positions of the hydrogen atoms into a pair of correlated rings. [ 1 ] In that state, the water molecules become delocalized around a ring and assume an unusual double top-like shape. At low... | https://en.wikipedia.org/wiki/Quantum_tunneling_of_water |
In physics, quantum tunnelling , barrier penetration , or simply tunnelling is a quantum mechanical phenomenon in which an object such as an electron or atom passes through a potential energy barrier that, according to classical mechanics , should not be passable due to the object not having sufficient energy to pass o... | https://en.wikipedia.org/wiki/Quantum_tunnelling |
In physics , a quantum vortex represents a quantized flux circulation of some physical quantity . In most cases, quantum vortices are a type of topological defect exhibited in superfluids and superconductors . The existence of quantum vortices was first predicted by Lars Onsager in 1949 in connection with superfluid he... | https://en.wikipedia.org/wiki/Quantum_vortex |
In particle physics , the quantum yield (denoted Φ ) of a radiation -induced process is the number of times a specific event occurs per photon absorbed by the system . [ 1 ]
Φ ( λ ) = number of events number of photons absorbed {\displaystyle \Phi (\lambda )={\frac {\text{ number of events }}{\text{ number of photons ... | https://en.wikipedia.org/wiki/Quantum_yield |
The quaquaversal tiling is a nonperiodic tiling of Euclidean 3-space introduced by John Conway and Charles Radin . It is analogous to the pinwheel tiling in 2 dimensions having tile orientations that are dense in SO(3) . The basic solid tiles are 30-60-90 triangular prisms arranged in a pattern such that some copies ar... | https://en.wikipedia.org/wiki/Quaquaversal_tiling |
In particle physics , the quark model is a classification scheme for hadrons in terms of their valence quarks —the quarks and antiquarks that give rise to the quantum numbers of the hadrons. The quark model underlies "flavor SU(3)" , or the Eightfold Way , the successful classification scheme organizing the large numb... | https://en.wikipedia.org/wiki/Quark_model |
A quark star is a hypothetical type of compact , exotic star , where extremely high core temperature and pressure have forced nuclear particles to form quark matter , a continuous state of matter consisting of free quarks . [ 1 ]
Some massive stars collapse to form neutron stars at the end of their life cycle , as has... | https://en.wikipedia.org/wiki/Quark_star |
Quark–gluon plasma ( QGP or quark soup ) is an interacting localized assembly of quarks and gluons at thermal (local kinetic) and (close to) chemical (abundance) equilibrium. The word plasma signals that free color charges are allowed. In a 1987 summary, Léon Van Hove pointed out the equivalence of the three terms: qua... | https://en.wikipedia.org/wiki/Quark–gluon_plasma |
A tub or quarry tub is a type of railway or tramway wagon used in quarries and other industrial locations for the transport of minerals (such as coal , sand , ore , clay and stone ) from a quarry or mine face to processing plants or between various parts of an industrial site. [ 1 ] This type of wagon may be small enou... | https://en.wikipedia.org/wiki/Quarry_tub |
In computing , a nibble , [ 1 ] or spelled nybble to match byte , is a unit of information that is an aggregation of four- bits ; half of a byte/ octet . [ 1 ] [ 2 ] [ 3 ] The unit is alternatively called nyble , nybl , half-byte [ 4 ] or tetrade . [ 5 ] [ 6 ] In networking or telecommunications , the unit is often cal... | https://en.wikipedia.org/wiki/Quartet_(computing) |
In mathematics , a quartic equation is one which can be expressed as a quartic function equaling zero. The general form of a quartic equation is
where a ≠ 0.
The quartic is the highest order polynomial equation that can be solved by radicals in the general case.
Lodovico Ferrari is attributed with the discovery of t... | https://en.wikipedia.org/wiki/Quartic_equation |
In algebra , a quartic function is a function of the form
where a is nonzero,
which is defined by a polynomial of degree four, called a quartic polynomial .
A quartic equation , or equation of the fourth degree, is an equation that equates a quartic polynomial to zero, of the form
where a ≠ 0 . [ 1 ] The derivative ... | https://en.wikipedia.org/wiki/Quartic_function |
Quartic or biquadratic reciprocity is a collection of theorems in elementary and algebraic number theory that state conditions under which the congruence x 4 ≡ p (mod q ) is solvable; the word "reciprocity" comes from the form of some of these theorems, in that they relate the solvability of the congruence x 4 ≡ p (mod... | https://en.wikipedia.org/wiki/Quartic_reciprocity |
Quartz dolerite or quartz diabase is an intrusive rock similar to dolerite (also called diabase), but with an excess of quartz . Dolerite is similar in composition to basalt , which is volcanic , and gabbro , which is plutonic . The differing crystal sizes are due to the different rate of cooling, basalt cools quickly ... | https://en.wikipedia.org/wiki/Quartz-dolerite |
Within surface science , a quartz crystal microbalance with dissipation monitoring ( QCM-D ) is a type of quartz crystal microbalance (QCM) based on the ring-down technique . It is used in interfacial acoustic sensing . Its most common application is the determination of a film thickness in a liquid environment (such ... | https://en.wikipedia.org/wiki/Quartz_crystal_microbalance_with_dissipation_monitoring |
A quasar ( / ˈ k w eɪ z ɑːr / KWAY -zar ) is an extremely luminous active galactic nucleus (AGN). It is sometimes known as a quasi-stellar object , abbreviated QSO . The emission from an AGN is powered by accretion onto a supermassive black hole with a mass ranging from millions to tens of billions of solar masses , su... | https://en.wikipedia.org/wiki/Quasar |
The Quasar Equatorial Survey Team ( QUEST ) is a joint venture between Yale University , Indiana University , and Centro de Investigaciones de Astronomia (CIDA) to photographically survey the sky using a digital camera , an array of 112 charge-coupled devices . Since 2009, it has used the 1 m ESO Schmidt Telescope in ... | https://en.wikipedia.org/wiki/Quasar_Equatorial_Survey_Team |
In mathematics , a quasi-Lie algebra in abstract algebra is just like a Lie algebra , but with the usual axiom
replaced by
In characteristic other than 2, these are equivalent (in the presence of bilinearity ), so this distinction doesn't arise when considering real or complex Lie algebras. It can however become impo... | https://en.wikipedia.org/wiki/Quasi-Lie_algebra |
In mathematics , the notion of a quasi-continuous function is similar to, but weaker than, the notion of a continuous function . All continuous functions are quasi-continuous but the converse is not true in general.
Let X {\displaystyle X} be a topological space . A real-valued function f : X → R {\displaystyle f:X\... | https://en.wikipedia.org/wiki/Quasi-continuous_function |
Quasi-crystals are supramolecular aggregates exhibiting both crystalline (solid) properties as well as amorphous, liquid-like properties.
Self-organized structures termed "quasi-crystals" were originally described in 1978 by the Israeli scientist Valeri A. Krongauz of the Weizmann Institute of Science , in the Nature ... | https://en.wikipedia.org/wiki/Quasi-crystals_(supramolecular) |
Quasi-empirical methods are scientific methods used to gain knowledge in situations where empirical evidence cannot be gathered through experimentation, or experience cannot falsify the ideas involved. Quasi-empirical methods aim to be as closely analogous to empirical methods as possible. [ 1 ]
Empirical research rel... | https://en.wikipedia.org/wiki/Quasi-empirical_method |
Quasi-empiricism in mathematics is the attempt in the philosophy of mathematics to direct philosophers' attention to mathematical practice , in particular, relations with physics , social sciences , and computational mathematics , rather than solely to issues in the foundations of mathematics . Of concern to this discu... | https://en.wikipedia.org/wiki/Quasi-empiricism_in_mathematics |
A linear differential operator L is called quasi-exactly-solvable ( QES ) if it has a finite-dimensional invariant subspace of functions { V } n {\displaystyle \{{\mathcal {V}}\}_{n}} such that L : { V } n → { V } n , {\displaystyle L:\{{\mathcal {V}}\}_{n}\rightarrow \{{\mathcal {V}}\}_{n},} where n is a dimension of ... | https://en.wikipedia.org/wiki/Quasi-exact_solvability |
Quasi-extinction refers to the state in which a species or population has declined to critically low numbers, making its recovery highly unlikely, even though a small number of individuals may still persist. This concept is often used in conservation biology to identify species at extreme risk of extinction and to guid... | https://en.wikipedia.org/wiki/Quasi-extinction |
The quasi-harmonic approximation is a phonon -based model of solid-state physics used to describe volume-dependent thermal effects, such as the thermal expansion . It is based on the assumption that the harmonic approximation holds for every value of the lattice constant , which is to be viewed as an adjustable paramet... | https://en.wikipedia.org/wiki/Quasi-harmonic_approximation |
In universal algebra , a quasi-identity is an implication of the form
where s 1 , ..., s n , t 1 , ..., t n , s , and t are terms built up from variables using the operation symbols of the specified signature .
A quasi-identity amounts to a conditional equation for which the conditions themselves are equations. Alter... | https://en.wikipedia.org/wiki/Quasi-identity |
In mathematics , a quasi-invariant measure μ with respect to a transformation T , from a measure space X to itself, is a measure which, roughly speaking, is multiplied by a numerical function of T . An important class of examples occurs when X is a smooth manifold M , T is a diffeomorphism of M , and μ is any measure t... | https://en.wikipedia.org/wiki/Quasi-invariant_measure |
Quasi-linkage equilibrium (QLE) is a mathematical approximation used in solving population genetics problems. Motoo Kimura introduced the notion to simplify a model of Fisher's fundamental theorem . QLE greatly simplifies population genetic equations whilst making the assumption of weak selection and weak epistasis . ... | https://en.wikipedia.org/wiki/Quasi-linkage_equilibrium |
The concept of a quasi-median network is a generalization of the concept of a median network that was introduced to represent multistate characters. Note that, unlike median networks, quasi-median networks are not split networks . A quasi-median network is defined as a phylogenetic network , the node set of which is gi... | https://en.wikipedia.org/wiki/Quasi-median_networks |
Quasi-opportunistic supercomputing is a computational paradigm for supercomputing on a large number of geographically disperse computers . [ 3 ] Quasi-opportunistic supercomputing aims to provide a higher quality of service than opportunistic resource sharing . [ 4 ]
The quasi-opportunistic approach coordinates comput... | https://en.wikipedia.org/wiki/Quasi-opportunistic_supercomputing |
A quasi-peak detector is a type of electronic detector or rectifier . Quasi-peak detectors for specific purposes have usually been standardized with mathematically precisely defined dynamic characteristics of attack time , integration time, and decay time or fall-back time.
Quasi-peak detectors play an important role ... | https://en.wikipedia.org/wiki/Quasi-peak_detector |
In mathematics , a quasi-polynomial ( pseudo-polynomial ) is a generalization of polynomials . While the coefficients of a polynomial come from a ring , the coefficients of quasi-polynomials are instead periodic functions with integral period. Quasi-polynomials appear throughout much of combinatorics as the enumerators... | https://en.wikipedia.org/wiki/Quasi-polynomial |
In topology , a branch of mathematics, the quasi-relative interior of a subset of a vector space is a refinement of the concept of the interior . Formally, if X {\displaystyle X} is a linear space then the quasi-relative interior of A ⊆ X {\displaystyle A\subseteq X} is qri ( A ) := { x ∈ A : c o n e ¯ ( A − x ) i... | https://en.wikipedia.org/wiki/Quasi-relative_interior |
Quasi-solid , false-solid , or partial-solid are terms for a substance which is not clearly a solid or a liquid . While similar to solids in some respects, such as having the ability to support their own weight and hold their shapes, a quasi-solid also shares some properties of liquids, such as conforming in shape to s... | https://en.wikipedia.org/wiki/Quasi-solid |
In mathematics , a quasicircle is a Jordan curve in the complex plane that is the image of a circle under a quasiconformal mapping of the plane onto itself. Originally introduced independently by Pfluger (1961) and Tienari (1962) , in the older literature (in German) they were referred to as quasiconformal curves , a t... | https://en.wikipedia.org/wiki/Quasicircle |
A quasiperiodic crystal , or quasicrystal , is a structure that is ordered but not periodic . A quasicrystalline pattern can continuously fill all available space, but it lacks translational symmetry . [ 2 ] While crystals, according to the classical crystallographic restriction theorem , can possess only two-, three-,... | https://en.wikipedia.org/wiki/Quasicrystal |
In physics, quasielastic scattering designates a limiting case of inelastic scattering , characterized by energy transfers being small compared to the incident energy of the scattered particles.
The term was originally coined in nuclear physics. [ 1 ]
It was applied to thermal neutron scattering by Leon van Hove [ 2 ... | https://en.wikipedia.org/wiki/Quasielastic_scattering |
In mathematics, quasilinearization is a technique which replaces a nonlinear differential equation or operator equation (or system of such equations) with a sequence of linear problems, which are presumed to be easier, and whose solutions approximate the solution of the original nonlinear problem with increasing accura... | https://en.wikipedia.org/wiki/Quasilinearization |
In linear algebra , functional analysis and related areas of mathematics , a quasinorm is similar to a norm in that it satisfies the norm axioms, except that the triangle inequality is replaced by ‖ x + y ‖ ≤ K ( ‖ x ‖ + ‖ y ‖ ) {\displaystyle \|x+y\|\leq K(\|x\|+\|y\|)} for some K > 1. {\displaystyle K>1.}
A quasi-se... | https://en.wikipedia.org/wiki/Quasinorm |
Quasinormal modes ( QNM ) are the modes of energy dissipation of a perturbed object or field, i.e. they describe perturbations of a field that decay in time.
A familiar example is the perturbation (gentle tap) of a wine glass with a knife: the glass begins to ring, it rings with a set, or superposition, of its natural... | https://en.wikipedia.org/wiki/Quasinormal_mode |
In condensed matter physics , a quasiparticle is a concept used to describe a collective behavior of a group of particles that can be treated as if they were a single particle. Formally, quasiparticles and collective excitations are closely related phenomena that arise when a microscopically complicated system such as ... | https://en.wikipedia.org/wiki/Quasiparticle |
In mathematics and theoretical physics , quasiperiodic motion is motion on a torus that never comes back to the same point. This behavior can also be called quasiperiodic evolution, dynamics, or flow . The torus may be a generalized torus so that the neighborhood of any point is more than two-dimensional. At each point... | https://en.wikipedia.org/wiki/Quasiperiodic_motion |
Quasiperiodicity is the property of a system that displays irregular periodicity . Periodic behavior is defined as recurring at regular intervals, such as "every 24 hours". [ 1 ] Quasiperiodic behavior is almost but not quite periodic. [ 2 ] The term used to denote oscillations that appear to follow a regular pattern b... | https://en.wikipedia.org/wiki/Quasiperiodicity |
In mathematics , a quasirandom group is a group that does not contain a large product-free [ clarification needed ] subset . Such groups are precisely those without a small non-trivial irreducible representation . The namesake of these groups stems from their connection to graph theory : bipartite Cayley graphs over an... | https://en.wikipedia.org/wiki/Quasirandom_group |
In the mathematical field of analysis , quasiregular maps are a class of continuous maps between Euclidean spaces R n of the same dimension or, more generally, between Riemannian manifolds of the same dimension, which share some of the basic properties with holomorphic functions of one complex variable.
The theory of ... | https://en.wikipedia.org/wiki/Quasiregular_map |
The quasispecies model is a description of the process of the Darwinian evolution of certain self-replicating entities within the framework of physical chemistry . A quasispecies is a large group or " cloud " of related genotypes that exist in an environment of high mutation rate (at stationary state [ 1 ] ), where a l... | https://en.wikipedia.org/wiki/Quasispecies_model |
Quasistatic approximation(s) refers to different domains and different meanings. In the most common acceptance, quasistatic approximation refers to equations that keep a static form (do not involve time derivatives ) even if some quantities are allowed to vary slowly with time. In electromagnetism it refers to mathemat... | https://en.wikipedia.org/wiki/Quasistatic_approximation |
In thermodynamics , a quasi-static process , also known as a quasi-equilibrium process (from Latin quasi , meaning ‘as if’ [ 1 ] ), is a thermodynamic process that happens slowly enough for the system to remain in internal physical (but not necessarily chemical) thermodynamic equilibrium . An example of this is quasi-s... | https://en.wikipedia.org/wiki/Quasistatic_process |
In algebra and in particular in algebraic combinatorics , a quasisymmetric function is any element in the ring of quasisymmetric functions which is in turn a subring of the formal power series ring with a countable number of variables. This ring generalizes the ring of symmetric functions . This ring can be realized... | https://en.wikipedia.org/wiki/Quasisymmetric_function |
In mathematics , a quasisymmetric homeomorphism between metric spaces is a map that generalizes bi-Lipschitz maps. While bi-Lipschitz maps shrink or expand the diameter of a set by no more than a multiplicative factor, quasisymmetric maps satisfy the weaker geometric property that they preserve the relative sizes of se... | https://en.wikipedia.org/wiki/Quasisymmetric_map |
In magnetic confinement fusion , quasisymmetry (sometimes hyphenated as quasi-symmetry ) is a type of continuous symmetry in the magnetic field strength of a stellarator . [ 1 ] Quasisymmetry is desired, as Noether's theorem implies that there exists a conserved quantity in such cases. This conserved quantity ensures t... | https://en.wikipedia.org/wiki/Quasisymmetry |
In mathematics , a quasi-topology on a set X is a function that associates to every compact Hausdorff space C a collection of mappings from C to X satisfying certain natural conditions. A set with a quasi-topology is called a quasitopological space .
They were introduced by Spanier, who showed that there is a natural ... | https://en.wikipedia.org/wiki/Quasitopological_space |
In mathematics , a quasitoric manifold is a topological analogue of the nonsingular projective toric variety of algebraic geometry . A smooth 2 n {\displaystyle 2n} -dimensional manifold is a quasitoric manifold if it admits a smooth, locally standard action of an n {\displaystyle n} -dimensional torus , with orbit spa... | https://en.wikipedia.org/wiki/Quasitoric_manifold |
Quaternary is a term used in organic chemistry to classify various types of compounds (e. g. amines and ammonium salts ). [ 1 ]
Quaternary central atoms compared with primary , secondary and tertiary central atoms. | https://en.wikipedia.org/wiki/Quaternary_(chemistry) |
A quaternary carbon is a carbon atom bound to four other carbon atoms. [ 1 ] For this reason, quaternary carbon atoms are found only in hydrocarbons having at least five carbon atoms. Quaternary carbon atoms can occur in branched alkanes , but not in linear alkanes. [ 2 ]
The formation of chiral quaternary carbon cent... | https://en.wikipedia.org/wiki/Quaternary_carbon |
In materials chemistry , a quaternary phase is a chemical compound containing four elements . Some compounds can be molecular or ionic, examples being chlorodifluoromethane ( CHClF 2 ) and sodium bicarbonate ( NaCO 3 H ). More typically quaternary phase refers to extended solids. A famous example are the yttrium bariu... | https://en.wikipedia.org/wiki/Quaternary_phase |
In differential geometry , a quaternion-Kähler symmetric space or Wolf space is a quaternion-Kähler manifold which, as a Riemannian manifold , is a Riemannian symmetric space . Any quaternion-Kähler symmetric space with positive Ricci curvature is compact and simply connected , and is a Riemannian product of quaternion... | https://en.wikipedia.org/wiki/Quaternion-Kähler_symmetric_space |
In mathematics , quaternionic analysis is the study of functions with quaternions as the domain and/or range. Such functions can be called functions of a quaternion variable just as functions of a real variable or a complex variable are called.
As with complex and real analysis , it is possible to study the concepts o... | https://en.wikipedia.org/wiki/Quaternionic_analysis |
A quaternionic matrix is a matrix whose elements are quaternions .
The quaternions form a noncommutative ring , and therefore addition and multiplication can be defined for quaternionic matrices as for matrices over any ring.
Addition . The sum of two quaternionic matrices A and B is defined in the usual way by eleme... | https://en.wikipedia.org/wiki/Quaternionic_matrix |
In geometry , a quaternionic polytope is a generalization of a polytope in real space to an analogous structure in a quaternionic module , where each real dimension is accompanied by three imaginary ones. Similarly to complex polytopes , points are not ordered and there is no sense of "between", and thus a quaternionic... | https://en.wikipedia.org/wiki/Quaternionic_polytope |
In mathematics , quaternionic projective space is an extension of the ideas of real projective space and complex projective space , to the case where coordinates lie in the ring of quaternions H . {\displaystyle \mathbb {H} .} Quaternionic projective space of dimension n is usually denoted by
and is a closed manifold ... | https://en.wikipedia.org/wiki/Quaternionic_projective_space |
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