antiparticle

Annihilation is defined as "total destruction" or "complete obliteration" of a particular object. Annihilation of an atomic or subatomic particle, occurs when such a particle collides with its respective antiparticle. If a particle and its respective antiparticle are both tuned to the appropriate quantum states, then they annihilate each other and their "destruction" yields other particles; usually into particles elementary of other particles. Nothing can ever be "annihilated" physically, as stipulated by its definition, as ...

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In physics, the W and Z bosons are the elementary particles that mediate the weak nuclear force. Their discovery at CERN in 1983 has been heralded as a major success for the Standard Model of particle physics. The W particle is named after the weak nuclear force. The Z particle was semi-humourously given its name because it was said to be the last particle to need discovery. Another explanation is that the Z particle derives its name from the fact that it has zero electric charge. W and Z bosons - Ba ...

Including:

• W and Z bosons - Basic properties
• W and Z bosons - The weak nuclear force
• W and Z bosons - Predicting the W and Z
• W and Z bosons - Discovery of the W and Z

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The charm quark is a second-generation quark with a charge of +(2/3)e. It is the third most massive of the quarks, at 1.3 GeV (a bit more than the mass of the proton). It was predicted in 1970 by Sheldon Glashow, John Iliopoulos, and Luciano Maiani, and first observed in 1974, with the simultaneous discovery of the J/ψ charm particle at SLAC by a group led by Burton Richter and at BNL by a group led by Samuel C. C. Ting. The particle was named J by the BNL group and ψ by the SLAC group; when the naming controversy could ...

Including:

• Charm quark - Hadrons containing charm quarks

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A subatomic particle is a particle smaller than an atom: it may be elementary or composite. Particle physics and nuclear physics concern themselves with the study of these particles, their interactions, and matter made up of them which do not aggregate into atoms. These particles include atomic constituents such as electrons, protons, and neutrons (protons and neutrons are actually composite particles, made up of quarks), as well as other particles such as photons and neutrinos which are produced copiously in the sun. However, ...

Including:

• Subatomic particle - Dividing an atom
• Subatomic particle - Classification of subatomic particles
• Subatomic particle - Elementary particles
• Subatomic particle - Conjectures and predictions
• Subatomic particle - Composite particles
• Subatomic particle - History

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The antiproton (aka pbar) is the antiparticle of the proton. Antiprotons are short-lived in nature, since any collision with a proton will cause both particles to be annihilated in a burst of energy. It was discovered in the year 1955 by University of California Berkeley Physicists Emilio Segre and Owen Chamberlain, for which they were awarded a 1959 Nobel Prize in Physics. Their formation requires energy equivalent to a temperature of 10 million °C, and Big Bangs aside, this does not tend to happen naturally. However, at CERN ...

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Anti can have multiple different meanings such as: The prefix anti- means "the opposite of". In particle physics, anti- refers to a particle with the same mass but opposite charges, an antiparticle. In Egyptian mythology, Anti was the ferryman who carried Isis to Set's island. Anti, or Campa is a tribe of South American Indians of Arawakan stock, inhabiting the forests of the upper Ucayali basin, east of Cuzco, on the eastern si

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Light is electromagnetic radiation with a wavelength that is visible to the eye (visible light) or, in a technical or scientific context, electromagnetic radiation of any wavelength. The three basic dimensions of light (i.e., all electromagnetic radiation) are: Intensity (or brilliance or amplitude), which is related to the human perception of brightness of the light, Frequency (or wavelength), perceived by humans as the color of the light, and Polarization (or angle of vibration), which is not perceptible by ...

Including:

• Light - Visible electromagnetic radiation
• Light - Speed of light
• Light - Refraction
• Light - Optics
• Light - Color and wavelengths
• Light - Measurement of light
• Light - Light sources
• Light - Theories about light
• Light - Early Greek ideas
• Light - 10th century optical theory
• Light - The 'plenum'
• Light - Particle theory
• Light - Wave theory
• Light - Electromagnetic theory
• Light - Particle theory revisited
• Light - Quantum theory
• Light - Wave-particle duality
• Light - A light wave

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In physics, a virtual particle is a loosely defined term that is frequently used to explain or illuminate a variety of disparate effects in quantum field theory. It usually refers to a field excitation mode that appears in an intermediate step in a calculation. The terms off-shell, off-shell particle or off-shell excitation are also commonly used. The term is used as a contrast with the idea of a real particleIncluding:

• Virtual particle - Virtual particles in Feynman diagrams
• Virtual particle - Virtual particles in the vacuum
• Virtual particle - Pair production
• Virtual particle - History

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In physics, and specifically particle physics, CP violation is a violation of the postulated CP symmetry of the laws of physics. It plays an important role in theories of cosmology that attempt to explain the dominance of matter over antimatter in the present Universe. The discovery of CP violation in 1964 in the decays of neutral kaons resulted in the Nobel Prize in Physics in 1980 for its discoverers James Cronin and Val Fitch. The study of CP violation remains a vibrant area of theoretical and exp ...

Including:

• CP-violation - What is CP?
• CP-violation - CP Violation
• CP-violation - CP Violation and the Existence of the Universe

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Beta particles are high-energy electrons or positrons emitted by certain types of radioactive nuclei such as potassium-40. The beta particles emitted are a form of ionizing radiation also known as beta rays. The production of beta particles is termed beta decay. They are designated by the Greek letter beta (β). There are two forms of beta decay, β− and β+, which respectively give rise to the electron and the positron. Beta particle - β− decay electron. Unstabl ...

Including:

• Beta particle - β⁻ decay electron
• Beta particle - β⁺ decay positron
• Beta particle - The neutrino and conservation of energy

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In physics, asymptotic freedom is the property of some gauge theories in which the interaction between the particles, such as quarks, becomes arbitrarily weak at ever shorter distances, i.e. length scales that asymptotically converge to zero (or, equivalently, energy scales that become arbitrarily large). Asymptotic freedom - Discovery. The fact that asymptotic freedom is a feature of quantum chromodynamics (QCD), the quantum field theory of the interactions of quarks and gluons, was discovered by David Gro ...

Including:

• Asymptotic freedom - Discovery
• Asymptotic freedom - Screening and antiscreening
• Asymptotic freedom - Calculating asymptotic freedom
• Asymptotic freedom - External link

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The path integral method is an alternative formulation of quantum mechanics. The canonical approach, pioneered by Schroedinger, Heisenberg and Dirac paid great attention to wave-particle duality and the resulting uncertainty principle by replacing Poisson brackets of classical mechanics by commutators between operators in quantum mechanics. The Hilbert space of quantum states and the superposition law of quantum amplitudes follows. The path integral starts from the superposition law, and exploits wave-particle duality to build a generating function for quantum amplitudes.See also:

Path integral formulation, Path integral formulation - Formulating quantum mechanics, Path integral formulation - Quantum amplitudes, Path integral formulation - Recovering the action principle, Path integral formulation - Time Slicing Definition, Path integral formulation - Particle in Curved Space, Path integral formulation - The path integral and the partition function, Path integral formulation - Quantum field theory, Path integral formulation - The propagator, Path integral formulation - Functionals of fields, Path integral formulation - Expectation values, Path integral formulation - Schwinger-Dyson equations, Path integral formulation - Ward-Takahashi identities, Path integral formulation - The path integral in quantum-mechanical interpretation, Path integral formulation - Suggested Reading, Path integral formulation - Papers on-line

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The antiproton is the antiparticle of the proton. It was discovered in the year 1955 by Emilio Segre and Owen Chamberlain, for which they were awarded a 1959 Nobel Prize in Physics. CPT-symmetry puts strong constraints on the relative properties of particles and antiparticles and, therefore, is open to stringent tests. For example, the charges of the proton and antiproton must sum to exactly zero. This equality has been tested to one part in 10-8. The equality of their masses is also tested to better than one ...

See also:

Proton, Proton - History, Proton - Technological applications, Proton - Antiproton

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An elementary particle is a particle with no measurable internal structure, that is, it is not a composite of other particles. They are the fundamental objects of Quantum Field Theory. Elementary particles can be classified according to their spin, with fermions having half-integer spin and bosons integer spin. List of particles - Standard Model. The Standard Model of particle physics is our current understanding of the physics of elementary particles. All Standard Model pa ...

See also:

List of particles, List of particles - Elementary particles, List of particles - Standard Model, List of particles - Hypothetical particles, List of particles - Composite particles, List of particles - Hadrons, List of particles - Atomic nuclei, List of particles - Atoms, List of particles - Molecules, List of particles - Condensed matter, List of particles - Other, List of particles - Categorisation by speed, List of particles - Reference

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Paul Dirac - Early years. Paul Dirac grew up in Bishopston, in the English city of Bristol. His father, Charles Dirac, was an immigrant from the Valais Canton in Switzerland who taught French for a living. His mother was originally from Cornwall and the daughter of a mariner. Paul had an elder brother and a younger sister. His early family life appears to have been unhappy on account of his father's unusually strict and authoritarian nature. He was educated first at Bishop Road Primary School and then at Merchant ...

See also:

Paul Dirac, Paul Dirac - Biography, Paul Dirac - Early years, Paul Dirac - Middle years, Paul Dirac - Later years, Paul Dirac - Death and afterwards, Paul Dirac - Views, Paul Dirac - Books by Dirac

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The most famous use of the positron in fiction was Isaac Asimov's use in his robots' positronic brains. It is likely that he chose to use positrons because they were relatively newly-discovered when he was first writing about the robots. Perhaps in an homage to Asimov, in the Star Trek universe the android Data, his "brother" Lore, "daughter" Lal, and other sundry related androids also have positronic brains. In Hideaki Anno's Neon Genesis Evangelion, the positron rifle, based upon the ATHENA tests in Europe, is used ...

See also:

Positron, Positron - The positron in fiction

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This function has some properties that seem baffling at first. In particular, unlike the commutator, the propagator is nonzero outside of the light cone, though it falls off rapidly for spacelike intervals. Interpreted as an amplitude for particle motion, this translates to the virtual particle traveling faster than light. It is not immediately obvious how this can be reconciled with causality: can we use faster-than-light virt ...

See also:

Propagator, Propagator - Momentum space propagator, Propagator - Position space propagator, Propagator - Faster than light?, Propagator - Propagators in Feynman diagrams, Propagator - Other theories

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The neutron interacts through all four of the common classifications of physical interaction. These four are the electromagnetic, weak nuclear, strong nuclear and gravitational interactions. Although it is true that the neutron has zero net charge, it is nonetheless composed of electrically charged quarks, in the same way that a neutral atom is nonetheless composed of protons and electrons. As such, the neutron experiences the electromagnetic interaction. The net charge is zero, so if you are far enough away from the neutron that it a ...

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Neutron, Neutron - Properties, Neutron - Neutron Interactions, Neutron - Neutron Detection, Neutron - Neutron Uses, Neutron - Neutron Sources, Neutron - Discovery, Neutron - Current developments, Neutron - Antineutron, Neutron - Fields concerning neutrons, Neutron - Types of neutrons, Neutron - Objects containing neutrons, Neutron - Neutron sources, Neutron - Processes involving neutrons

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Two kinds of W bosons exist with +1 and −1 elementary units of electric charge; the W+ is the antiparticle of the W−. The Z boson (or Z0) is electrically neutral and is its own antiparticle. All three particles are very short-lived with a mean life of about 3 × 10−25 seconds. These bosons are heavyweights among the elementary particles. With a mass of 80.4 and 91.2 GeV/c2, respectively, the W and Z particles are almost 100 times as massive as the proton—hea ...

See also:

W and Z bosons, W and Z bosons - Basic properties, W and Z bosons - The weak nuclear force, W and Z bosons - Predicting the W and Z, W and Z bosons - Discovery of the W and Z

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Initially it was thought that although parity was violated, CP symmetry was conserved (by kaons and everything else). In order to understand the discovery of CP violation, it is necessary to understand the mixing of neutral kaons; this phenomenon does not require CP violation, but it is the context in which CP violation was first observed. Kaon - Neutral kaon mixing. Since neutral kaons carry strangeness, they cannot be their own antiparticles. There must be then two different neutral kaons, differing by t ...

See also:

Kaon, Kaon - Basic properties, Kaon - Strangeness, Kaon - Parity violation: the τ-θ puzzle, Kaon - CP violation in neutral meson oscillations, Kaon - Neutral kaon mixing, Kaon - CP violation

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