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quantum and field
A unified interpretation of antiparticles is now available in quantum field theory, which solves both these problems.
This is an example of renormalization in quantum field theory the field theory being necessary because the number of particles changes from one to two and back again.
In quantum field theory, this process is allowed only as an intermediate quantum state for times short enough that the violation of energy conservation can be accommodated by the uncertainty principle.
These processes are important in the vacuum state and renormalization of a quantum field theory.
This section draws upon the ideas, language and notation of canonical quantization of a quantum field theory.
This technique is the most widespread method of computing amplitudes in quantum field theory today.
Practical applications are made impossible due to the no-cloning theorem, and the fact that quantum field theories preserve causality, so that quantum correlations cannot be used to transfer information.
The analogy was completed when Hawking, in 1974, showed that quantum field theory predicts that black holes should radiate like a black body with a temperature proportional to the surface gravity of the black hole.
* Canonical anticommutation relation, a concept in quantum field theory
The physical model behind cosmic inflation is extremely simple, however it has not yet been confirmed by particle physics, and there are difficult problems reconciling inflation and quantum field theory.
* An introduction including more on general relativity and quantum field theory than most.
After World War II, several ideas from quantum field theory were applied to condensed matter problems.
These ideas were unified by Kenneth Wilson in 1972, under the formalism of the renormalization group in the context of quantum field theory.
Theoretical models have also been developed to study the physics of phase transitions, such as the Landau-Ginzburg theory, Critical exponents and the use of mathematical techniques of quantum field theory and the renormalization group.
Goldstone's theorem in quantum field theory states that in a system with broken continuous symmetry, there may exist excitations with arbitrarily low energy, called the Goldstone bosons.
In 1929, Heisenberg gave a series of invited lectures at the University of Chicago explaining the new field of quantum mechanics.
The problem of thinking in terms of classical measurements of a quantum system becomes particularly acute in the field of quantum cosmology, where the quantum system is the universe.
The general concept of a chemical reaction has been extended to non-chemical reactions between entities smaller than atoms, including nuclear reactions, radioactive decays, and reactions between elementary particles as described by quantum field theory.
In quantum field theory, the Casimir effect and the Casimir – Polder force are physical forces arising from a quantized field.

quantum and theory
He discovered that the so-called Weil representation, previously introduced in quantum mechanics by Irving Segal and Shale, gave a contemporary framework for understanding the classical theory of quadratic forms.
A 2008 quantum physics experiment performed in Geneva, Switzerland has determined that in any hypothetical nonlocal hidden-variables theory the speed of the quantum non-local connection would have to be at least 10, 000 times the speed of light.
Sakharov also proposed the idea of induced gravity as an alternative theory of quantum gravity.
In computational complexity theory, BQP ( bounded error quantum polynomial time ) is the class of decision problems solvable by a quantum computer in polynomial time, with an error probability of at most 1 / 3 for all instances.
Apparently a new unified theory of quantum gravitation is needed to break this barrier.
Bootstrapping is using very general consistency criteria to determine the form of a quantum theory from some assumptions on the spectrum of particles.
Linear operators are ubiquitous in the theory of quantum mechanics.
Albert Einstein, in 1922, said regarding contemporary theories of superconductivity that “ with our far-reaching ignorance of the quantum mechanics of composite systems we are very far from being able to compose a theory out of these vague ideas ”

quantum and could
With the development of quantum mechanics, it was found that the orbiting electrons around a nucleus could not be fully described as particles, but needed to be explained by the wave-particle duality.
When Alaska Natives enrolled in their regional corporations under the terms of the Alaska Native Claims Settlement Act of 1971 ( ANCSA ), the Aleut Corporation attracted only about 2, 000 enrolees who could prove a blood quantum of 1 / 4 or more Alaska Native ( including Aleut ).
Recent papers by Guerreshi, G., Cia, J., Popescu, S. and Briegel, H. could falsify proposals such those of Hameroff which rely on quantum entanglement in protein.
The completeness of quantum mechanics ( thesis 1 ) was attacked by the Einstein-Podolsky-Rosen thought experiment which was intended to show that quantum physics could not be a complete theory.
This work showed that the quantum approach to chemical bonds could be fundamentally and quantitatively correct, but the mathematical methods used could not be extended to molecules containing more than one electron.
This calculation convinced the scientific community that quantum theory could give agreement with experiment.
Einstein struggled to the end of his life for a theory that could better comply with his idea of causality, protesting against the view that there exists no objective physical reality other than that which is revealed through measurement interpreted in terms of quantum mechanical formalism.
In quantum computation, entangled quantum states are used to perform computations in parallel, which may allow certain calculations to be performed much more quickly than they ever could be with classical computers.
Dyson's paper and also his lectures presented Feynman's theories of QED ( quantum electrodynamics ) in a form that other physicists could understand and undoubtedly facilitated the physics community's acceptance of Feynman's work.
This could explain why all known fermions have baryon or lepton quantum numbers and provide a physical mechanism for the Pauli exclusion principle.
With the advent of quantum physics, some scientists believed the concept of matter had merely changed, while others believed the conventional position could no longer be maintained.
Using quantum theory Dirac showed that if magnetic monopoles exist, then one could explain the quantization of electric charge --- that is, why the observed elementary particles carry charges that are multiples of the charge of the electron.
This means that the use of fluorescent quantum dots could produce a higher contrast image and at a lower cost than today's organic dyes used as contrast media.
Some research has suggested that if loop quantum gravity is correct, then naked singularities could exist in nature, implying that the cosmic censorship hypothesis does not hold.
That is, problems likely exist that an NTM could efficiently solve but that a quantum computer cannot.
Nevertheless, consider the EPR thought experiment, and suppose quantum states could be cloned.
When it was found in 1900 by Max Planck that the energy of waves could be described as consisting of small packets or " quanta ", Albert Einstein further developed this idea to show that an electromagnetic wave such as light could be described as a particle ( later called the photon ) with a discrete quantum of energy that was dependent on its frequency.
The quantum theory of the atom was developed as an explanation for the electron remaining in its orbit, which could not be explained by Newton's laws of motion and Maxwell's laws of ( classical ) electromagnetism.
This was 1935, but in 1964 it was shown by John Bell ( see Bell inequality ) that-although Einstein was correct in identifying seemingly paradoxical implications of quantum mechanical nonlocality-these implications could be experimentally tested.
The history of quantum chemistry essentially began with the 1838 discovery of cathode rays by Michael Faraday, the 1859 statement of the black body radiation problem by Gustav Kirchhoff, the 1877 suggestion by Ludwig Boltzmann that the energy states of a physical system could be discrete, and the 1900 quantum hypothesis by Max Planck that any energy radiating atomic system can theoretically be divided into a number of discrete energy elements ε such that each of these energy elements is proportional to the frequency ν with which they each individually radiate energy and a numerical value called Planck ’ s Constant.

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