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

* Quantum superpositions can be described as vector sums of the constituent states.

* Optics-based quantum computer ( Quantum optics ) ( qubits realized by appropriate states of different modes of the electromagnetic field, e. g. )

Quantum communication involves encoding information in quantum states, or qubits, as opposed to classical communication's use of bits.

Quantum key distribution exploits certain properties of these quantum states to ensure its security.

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

* Quantum biophysics involves quantum information processing of coherent states, entanglement between coherent protons and transcriptase components, and replication of decohered isomers to yield time-dependent base substitutions.

Quantum mechanics states that electrons in an atom cannot take on any arbitrary energy value.

Quantum states that give unitary representations of time reversal, i. e., have T < sup > 2 </ sup >= 1, are characterized by a multiplicative quantum number, sometimes called the T-parity.

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 ).

Such coherent states are part of the explanation of effects such as the Quantum Hall effect in low-temperature superconducting semiconductors.

* Quantum states of the light field

* Glauber States: Coherent states of Quantum Harmonic Oscillator

Quantum theory states that orbiting electrons of an atom must occupy discrete energy levels in order to be stable.

Quantum mechanics is described according to von Neumann ; in particular, the pure states are given by the rays, i. e. the one-dimensional subspaces, of some separable complex Hilbert space.

Quantum field theory states that all fundamental fields, such as the electromagnetic field, must be quantized at each and every point in space.

Quantum confinement is responsible for the increase of energy difference between energy states and band gap.

Quantum superpositions of these states can be taken such that they transform under rotations just like the spatial components of a rotating vector.

* electrons moving along edge states in the fractional Quantum Hall Effect

However even though most of the photons are not detectable they can't be ignored in the theory ; Quantum electrodynamic calculations show that the transition amplitude between any states with a finite number of photons vanishes.

* Quantum nonlocality arising from measurement correlations on quantum entangled states

Quantum theory predicts that states in a Hilbert space do not need to transform under representations of the group of rotations, but only under projective representations.

Quantum Darwinism is a theory explaining the emergence of the classical world from the quantum world as due to a process of Darwinian natural selection ; where the many possible quantum states are selected against in favor of a stable pointer state.

Quantum theory tells us that every particle exhibits wave properties.

EPR tried to set up a paradox to question the range of true application of Quantum Mechanics: Quantum theory predicts that both values cannot be known for a particle, and yet the EPR thought experiment purports to show that they must all have determinate values.

; Quantum mechanics or Particle physics: When a spinless particle ( or even an unpolarized particle with spin ) decays, the resulting decay distribution must be isotropic in the rest frame of the decaying particle regardless of the detailed physics of the decay.

Quantum field theories are used in many contexts, and are especially vital in elementary particle physics, where the particle count / number may change over the course of a reaction.

Quantum field theory depends on particle fields embedded in the flat space-time of special relativity.

Quantum entanglement occurs when particles such as photons, electrons, molecules as large as buckyballs ,< ref > Nature: Wave – particle duality of C < sub > 60 </ sub > molecules, 14 October 1999.

* Quantum tunneling, the quantum-mechanical effect where a particle crosses through a classically-forbidden potential energy barrier

Quantum physicists also use this convention of handedness because it is consistent with their convention of handedness for a particle ’ s spin.

Quantum mechanically it is not unreasonable to assume that the momenta of the electrons and nuclei in a molecule are comparable in magnitude ( recall that the corresponding operators do not contain mass and think of the molecule as a box containing the electrons and nuclei and see particle in a box ).

Quantum indeterminacy can also be illustrated in terms of a particle with a definitely measured momentum for which there must be a fundamental limit to how precisely its location can be specified.

Quantum mechanics ascribes a special significance to the wave packet: it is interpreted as a " probability wave ", describing the probability that a particle or particles in a particular state will be measured to have a given position and momentum.

" Fredkin answers his own question, " If so, we have to rethink particle disintegrations, inelastic collisions and Quantum Mechanics to better understand what is happening to the information.

Quantum tunnelling refers to the quantum mechanical phenomenon where a particle tunnels through a barrier that it classically could not surmount.

This is why, it is first shown how the translation operator is acting on a particle at position x ( the particle is then in the state according to Quantum Mechanics ).

Gollin has worked on particle physics experiments studying muon scattering ( 1975 – 1981, intended to test the ideas of " Quantum Chromodynamics "), neutral K meson decay parameters ( 1980 – 1993, measuring things relating to " CP violation "), and electron-positron annihilation ( 1993 – 2005, measuring production and decay properties of heavy quarks ).

Quantum chromodynamics ( QCD ), the theory of strong particle interactions, provides the best known example in nature ; see the article on the QCD vacuum for details.

Perturbative QCD is a subfield of particle physics in which the theory of strong interactions, Quantum Chromodynamics ( QCD ), is studied by using the fact that the strong coupling constant is small in high energy or short distance interactions, thus allowing Perturbation theory techniques to be applied.

Quantum mechanics can be used to describe spacetime as being non-empty at extremely small scales, fluctuating and generating particle pairs that appear and disappear incredibly quickly.

Quantum chromodynamics indicates that this particle is a particularly energetic gluon, radiated by one of the quarks, which hadronizes much as a quark does.