Quantum tomography is applied on a source of systems, to determine what the quantum state is of the output of that source.

Quantum tomography can be used for characterizing optical signals, including measuring the signal gain and loss of optical devices, as well as in quantum computing and quantum information theory to reliably determine the actual states of the qubits.

Quantum process tomography ( QPT ) deals with identifying an unknown quantum dynamical process.

# REDIRECT Quantum tomography

* Quantum annealing, a method for finding solutions to combinatorial optimisation problems and ground states of glassy systems using quantum fluctuations

According to a poll at a Quantum Mechanics workshop in 1997 ,< ref > the Copenhagen interpretation is the most widely-accepted specific interpretation of quantum mechanics, followed by the many-worlds interpretation.

The books that were influential in the early development of computational quantum chemistry include Linus Pauling and E. Bright Wilson's 1935 Introduction to Quantum Mechanics – with Applications to Chemistry, Eyring, Walter and Kimball's 1944 Quantum Chemistry, Heitler's 1945 Elementary Wave Mechanics – with Applications to Quantum Chemistry, and later Coulson's 1952 textbook Valence, each of which served as primary references for chemists in the decades to follow.

The idea of MWI originated in Everett's Princeton Ph. D. thesis " The Theory of the Universal Wavefunction ", developed under his thesis advisor John Archibald Wheeler, a shorter summary of which was published in 1957 entitled " Relative State Formulation of Quantum Mechanics " ( Wheeler contributed the title " relative state "; Everett originally called his approach the " Correlation Interpretation ", where " correlation " refers to quantum entanglement ).

Quantum theory and quantum mechanics do not provide single measurement outcomes in a deterministic way.

Bernard d ' Espagnat a French theoretical physicist best known for his work on the nature of reality wrote a paper titled The Quantum Theory and Reality according to the paper: " The doctrine that the world is made up of objects whose existence is independent of human consciousness turns out to be in conflict with quantum mechanics and with facts established by experiment.

* Quantum mass manifests itself as a difference between an object ’ s quantum frequency and its wave number.

Quantum field theory has driven the development of more sophisticated formulations of quantum mechanics, of which the one presented here is a simple special case.

* Quantum logic formulation of quantum mechanics

Quantum dots ( nanoparticles with quantum confinement properties, such as size-tunable light emission ), when used in conjunction with MRI ( magnetic resonance imaging ), can produce exceptional images of tumor sites.

Quantum optics deals with the application of quantum mechanics to optical systems.

* Quantum oscillator may refer to an optical local oscillator, as well as to a usual model in quantum optics.

* Quantum mechanics: In quantum mechanics, which deals with the behavior of very small objects, it is not possible to observe a system without changing the system, and the " observer " must be considered part of the system being observed.

Quantum chemistry, a subfield of physical chemistry especially concerned with the application of quantum mechanics to chemical problems, provides tools to determine how strong and what shape bonds are, how nuclei move, and how light can be absorbed or emitted by a chemical compound.

Quantum mechanics ( QM – also known as quantum physics, or quantum theory ) is a branch of physics dealing with physical phenomena at microscopic scales, where the action is on the order of the Planck constant.

Quantum mechanics departs from classical mechanics primarily at the quantum realm of atomic and subatomic length scales.

Quantum mechanics has since branched out into almost every aspect of 20th century physics and other disciplines, such as quantum chemistry, quantum electronics, quantum optics, and quantum information science.

Quantum coherence is an essential difference between classical and quantum theories, and is illustrated by the Einstein-Podolsky-Rosen paradox.

Quantum coherence is not typically evident at macroscopic scales-although an exception to this rule can occur at extremely low temperatures ( i. e. approaching absolute zero ), when quantum behavior can manifest itself on more macroscopic scales ( see macroscopic quantum phenomena, Bose-Einstein condensate, and Quantum machine ).

In his article entitled " Criticism and Counterproposals to the Copenhagen Interpretation of Quantum Theory ," countering the view of Alexandrov that ( in Heisenberg's paraphrase ) " the wave function in configuration space characterizes the objective state of the electron.

* Quantum chemistry and solid state physics software supporting several methods.

* Quantum state

" In an article in the Guardian titled Quantum weirdness: What we call ' reality ' is just a state of mind d ' Espagnat wrote that:

Quantum computers share theoretical similarities with non-deterministic and probabilistic computers, like the ability to be in more than one state simultaneously.

Quantum mechanically, we measure the three-qubit state, which is equivalent to collapsing the quantum state down to a classical distribution ( with the coefficients in the classical state being the squared magnitudes of the coefficients for the quantum state, as described above ), followed by sampling from that distribution.

* Chemistry: Molecular theory — Kinetic theory of gases — Molecular orbital theory — Valence bond theory — Transition state theory — RRKM theory — Chemical graph theory — Flory-Huggins solution theory — Marcus theory — Lewis theory ( successor to Brønsted – Lowry acid – base theory ) — HSAB theory — Debye – Hückel theory — Thermodynamic theory of polymer elasticity — Reptation theory — Polymer field theory — Møller – Plesset perturbation theory — Density Functional Theory — Frontier molecular orbital theory — Polyhedral skeletal electron pair theory — Baeyer strain theory — Quantum theory of atoms in molecules — Collision theory — Ligand field theory ( successor to Crystal field theory ) — Variational Transition State Theory — Benson group increment theory — Specific ion interaction theory

* Quantum Zeno effect, an effect in quantum mechanics which disallows certain conditions in the decaying of a quantum state

This is a derivation of the Quantum Hall state of matter.

Quantum indeterminacy means that these states cannot in general be measured without disturbing the original state ( see No cloning theorem ).

Quantum mechanically, this can be described as an excitation to a higher energy state and then a return to a lower energy state accompanied by the emission of a photon.

Quantum indeterminacy is the assertion that the state of a system does not determine a unique collection of values for all its measurable properties.

* Quantum state intentionally altered in molecule

* Quantum state in macroscopic object

Quantum mechanics is also not " local ", essentially because the state of a system is described by the Hilbert vector, which includes the value at every site,.

Quantum information specifies the complete quantum state vector ( or equivalently, wavefunction ) of a system, whereas classical information, roughly speaking, only picks out a definite ( pure ) quantum state if we are already given a prespecified set of distinguishable ( orthogonal ) quantum states to choose from ; such a set forms a basis for the vector space of all the possible pure quantum states ( see pure state ).

Quantum information could thus be expressed by providing ( 1 ) a choice of a basis such that the actual quantum state is equal to one of the basis vectors, together with ( 2 ) the classical information specifying which of these basis vectors is the actual one.

* Quantum state, in physics, the state of a quantum mechanical system given by a vector in the underlying Hilbert space