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Encyclopedia > Elementary particle

In particle physics, an elementary particle or fundamental particle is a particle not known to have substructure; that is, it is not known to be made up of smaller particles. If an elementary particle truly has no substructure, then it is one of the basic particles of the universe from which all larger particles are made. In the Standard Model, the quarks, leptons, and gauge bosons are elementary particles.[1][2] Les Particules Élémentaires (The Elementary Particles) is a novel by the French author Michel Houellebecq, published in France in 1998. ... Thousands of particles explode from the collision point of two relativistic (100 GeV per nucleon) gold ions in the STAR detector of the Relativistic Heavy Ion Collider. ... For other uses, see Universe (disambiguation). ... The Standard Model of Fundamental Particles and Interactions For the Standard Model in Cryptography, see Standard Model (cryptography). ... For other uses, see Quark (disambiguation). ... In physics, a lepton is a particle with spin-1/2 (a fermion) that does not experience the strong interaction (that is, the strong nuclear force). ... Gauge bosons are bosonic particles which act as carriers of the fundamental forces of Nature. ...


Historically, the hadrons (mesons and baryons such as the proton and neutron) and even whole atoms were once regarded as elementary particles. A central feature in elementary particle theory is the early 20th century idea of "quanta", which revolutionised the understanding of electromagnetic radiation and brought about quantum mechanics. A hadron, in particle physics, is a subatomic particle which experiences the nuclear force. ... Mesons of spin 1 form a nonet In particle physics, a meson is a strongly interacting boson, that is, it is a hadron with integral spin. ... Combinations of three u, d or s-quarks with a total spin of 3/2 form the so-called baryon decuplet. ... For other uses, see Proton (disambiguation). ... This article or section does not adequately cite its references or sources. ... For other uses, see Atom (disambiguation). ... In physics, a quantum (plural: quanta) is an indivisible entity of energy. ... Electromagnetic waves can be imagined as a self-propagating transverse oscillating wave of electric and magnetic fields. ... For a less technical and generally accessible introduction to the topic, see Introduction to quantum mechanics. ...

The Standard Model of Fundamental Particles and Interactions

Contents

Download high resolution version (3000x2275, 1444 KB)The Standard Model of Fundamental Particles and Interactions chart, copyright 2000 by the Contemporary Physics Education Project. ... Download high resolution version (3000x2275, 1444 KB)The Standard Model of Fundamental Particles and Interactions chart, copyright 2000 by the Contemporary Physics Education Project. ...

Overview

All elementary particles are either bosons or fermions (depending on their spin). The spin-statistics theorem identifies the resulting quantum statistics that differentiates fermions from bosons. According to this methodology: particles normally associated with matter are fermions, having half-integer spin; they are divided into twelve flavours. Particles associated with fundamental forces are bosons, having integer spin.[3] In particle physics, bosons, named after Satyendra Nath Bose, are particles having integer spin. ... In particle physics, fermions are particles with half-integer spin, such as protons and electrons. ... In physics, spin refers to the angular momentum intrinsic to a body, as opposed to orbital angular momentum, which is the motion of its center of mass about an external point. ... The spin-statistics theorem in quantum mechanics relates the spin of a particle to the statistics obeyed by that particle. ... Statistics of interacting identical particles (=when their wave functions overlap). ... This article is about matter in physics and chemistry. ... In particle physics, fermions are particles with half-integer spin, such as protons and electrons. ... In mathematics, a half-integer is a number of the form , where is an integer. ... Flavour (or flavor) is a quantum number of elementary particles related to their weak interactions. ... A fundamental interaction is a mechanism by which particles interact with each other, and which cannot be explained by another more fundamental interaction. ... In particle physics, bosons, named after Satyendra Nath Bose, are particles having integer spin. ... The integers are commonly denoted by the above symbol. ...

Quarksup, down, strange, charm, bottom, top
Leptonselectron, muon, tau, electron neutrino, muon neutrino, tau neutrino
Gauge bosonsgluon, W and Z bosons, photon
Other bosons — Higgs boson, graviton

In particle physics, fermions are particles with half-integer spin, such as protons and electrons. ... For other uses, see Quark (disambiguation). ... The up quark is a first-generation quark with a charge of +(2/3)e. ... The down quark is a first-generation quark with a charge of -(1/3)e. ... The strange quark is a second-generation quark with a charge of -(1/3)e and a strangeness of −1. ... The charm quark is a second-generation quark with a charge of +(2/3)e. ... The bottom quark is a third-generation quark with a charge of -(1/3)e. ... The top quark is the third-generation up-type quark with a charge of +(2/3)e. ... In physics, a lepton is a particle with spin-1/2 (a fermion) that does not experience the strong interaction (that is, the strong nuclear force). ... For other uses, see Electron (disambiguation). ... The muon (from the letter mu (μ)--used to represent it) is an elementary particle with negative electric charge and a spin of 1/2. ... The tau lepton (often called the tau or occasionally the tauon) is a negatively charged elementary particle with a lifetime of 3×10−13 seconds and a high mass of 1777 MeV (compared to 939 MeV for protons and 0. ... The neutrino is an elementary particle. ... The neutrino is an elementary particle. ... The neutrino is an elementary particle. ... In particle physics, bosons, named after Satyendra Nath Bose, are particles having integer spin. ... Gauge bosons are bosonic particles which act as carriers of the fundamental forces of Nature. ... In particle physics, gluons are subatomic particles that cause quarks to interact, and are indirectly responsible for the binding of protons and neutrons together in atomic nuclei. ... In physics, the W and Z bosons are the elementary particles that mediate the weak nuclear force. ... In modern physics the photon is the elementary particle responsible for electromagnetic phenomena. ... The Higgs boson is a hypothetical massive scalar elementary particle predicted to exist by the Standard Model of particle physics. ... This article is about the hypothetical particle. ...

Standard Model

Main article: Standard Model

The Standard Model of particle physics contains 12 flavours of elementary fermions, plus their corresponding antiparticles, as well as elementary bosons that mediate the forces and the still undiscovered Higgs boson. However, the Standard Model is widely considered to be a provisional theory rather than a truly fundamental one, since it is fundamentally incompatible with Einstein's general relativity. There are likely to be hypothetical elementary particles not described by the Standard Model, such as the graviton, the particle that would carry the gravitational force or the sparticles, supersymmetric partners of the ordinary particles. The Standard Model of Fundamental Particles and Interactions For the Standard Model in Cryptography, see Standard Model (cryptography). ... In particle physics, fermions are particles with half-integer spin, such as protons and electrons. ... Corresponding to most kinds of particle, there is an associated antiparticle with the same mass and opposite charges. ... In particle physics, bosons, named after Satyendra Nath Bose, are particles having integer spin. ... The Higgs boson is a hypothetical massive scalar elementary particle predicted to exist by the Standard Model of particle physics. ... “Einstein” redirects here. ... For a less technical and generally accessible introduction to the topic, see Introduction to general relativity. ... This article is about the hypothetical particle. ... Gravity is a force of attraction that acts between bodies that have mass. ... Sparticle is a merging of the words supersymmetric and particle. ... This article or section is in need of attention from an expert on the subject. ...


Fundamental fermions

Main article: fermion

The 12 fundamental fermionic flavours are divided into three generations of four particles each. Six of the particles are quarks. The remaining six are leptons, three of which are neutrinos, and the remaining three of which have an electric charge of −1: the electron and its two cousins, the muon and the tau lepton. In particle physics, fermions are particles with half-integer spin, such as protons and electrons. ... In particle physics, a generation is a division of the elementary particles. ... For other uses of this term, see: Quark (disambiguation) 1974 discovery photograph of a possible charmed baryon, now identified as the Σc++ In particle physics, the quarks are subatomic particles thought to be elemental and indivisible. ... A lepton is also a unit of currency. ... For other uses, see Neutrino (disambiguation). ... The muon (from the letter mu (μ)--used to represent it) is an elementary particle with negative electric charge and a spin of 1/2. ... The tau lepton (often called the tau or occasionally the tauon) is a negatively charged elementary particle with a lifetime of 3×10−13 seconds and a high mass of 1777 MeV (compared to 939 MeV for protons and 0. ...

Particle Generations
First generation Second generation Third generation

For other uses, see Electron (disambiguation). ... The neutrino is an elementary particle. ... The up quark is a first-generation quark with a charge of +(2/3)e. ... The down quark is a first-generation quark with a charge of -(1/3)e. ... The muon (from the letter mu (μ)--used to represent it) is an elementary particle with negative electric charge and a spin of 1/2. ... The neutrino is an elementary particle. ... The charm quark is a second-generation quark with a charge of +(2/3)e. ... The strange quark is a second-generation quark with a charge of -(1/3)e and a strangeness of −1. ... The tau lepton (often called the tau or occasionally the tauon) is a negatively charged elementary particle with a lifetime of 3×10−13 seconds and a high mass of 1777 MeV (compared to 939 MeV for protons and 0. ... The neutrino is an elementary particle. ... The top quark is the third-generation up-type quark with a charge of +(2/3)e. ... The bottom quark is a third-generation quark with a charge of -(1/3)e. ...

Antiparticles

Main article: antimatter

There are also 12 fundamental fermionic antiparticles which correspond to these 12 particles. The positron e+ corresponds to the electron and has an electric charge of +1 and so on: For other senses of this term, see antimatter (disambiguation). ... The first detection of the positron in 1932 by Carl D. Anderson The positron is the antiparticle or the antimatter counterpart of the electron. ...

Antiparticles
First generation
  • positron: e+
  • electron-antineutrino:  bar{nu}_e
  • up antiquark:  bar{u}
  • down antiquark:  bar{d}
Second generation
  • positive muon: μ+
  • muon-antineutrino:  bar{nu}_mu
  • charm antiquark:  bar{c}
  • strange antiquark:  bar{s}
Third generation
  • positive tau: τ+
  • tau-antineutrino:  bar{nu}_tau
  • top antiquark:  bar{t}
  • bottom antiquark:  bar{b}

The first detection of the positron in 1932 by Carl D. Anderson The positron is the antiparticle or the antimatter counterpart of the electron. ...

Quarks

Main article: quark

Quarks and antiquarks have never been detected to be isolated, a fact explained by confinement. Every quark carries one of three color charges of the strong interaction; antiquarks similarly carry anticolor. Color charged particles interact via gluon exchange in the same way that charged particles interact via photon exchange. However, gluons are themselves color charged, resulting in an amplification of the strong force as color charged particles are separated. Unlike the electromagnetic force which diminishes as charged particles separate, color charged particles feel increasing force; effectively, they very rarely separate from one another (and when they do they create an energy carrier particle which later converts to two new quarks of different type). For other uses, see Quark (disambiguation). ... Colour confinement (often just confinement) is the physics phenomenon that color charged particles (such as quarks) cannot be isolated. ... In quantum chromodynamics (QCD), color or color charge refers to a certain property of the subatomic particles called quarks. ... The strong interaction or strong force is today understood to represent the interactions between quarks and gluons as detailed by the theory of quantum chromodynamics (QCD). ... In particle physics, gluons are subatomic particles that cause quarks to interact, and are indirectly responsible for the binding of protons and neutrons together in atomic nuclei. ... In modern physics the photon is the elementary particle responsible for electromagnetic phenomena. ... Electromagnetism is the physics of the electromagnetic field: a field which exerts a force on particles that possess the property of electric charge, and is in turn affected by the presence and motion of those particles. ...


However, color charged particles may combine to form color neutral composite particles called hadrons. A quark may pair up to an antiquark: the quark has a color and the antiquark has the corresponding anticolor. The color and anticolor cancel out, forming a color neutral meson. Or three quarks can exist together: one quark is "red", another "blue", another "green". These three colored quarks together form a color neutral baryon. Or three antiquarks can exist together: one antiquark is "antired", another "antiblue", another "antigreen". These three anticolored antiquarks form a color neutral antibaryon. Elementary particles An elementary particle is a particle with no measurable internal structure, that is, it is not a composite of other particles. ... A hadron, in particle physics, is a subatomic particle which experiences the nuclear force. ... Mesons of spin 1 form a nonet In particle physics, a meson is a strongly interacting boson, that is, it is a hadron with integral spin. ... Combinations of three u, d or s-quarks with a total spin of 3/2 form the so-called baryon decuplet. ... The octet of light spin-1/2 baryons. ...


Quarks also carry fractional electric charges, but since they are confined within hadrons whose charges are all integral, fractional charges have never been isolated. Note that quarks have electric charges of either +2/3 or −1/3, whereas antiquarks have corresponding electric charges of either −2/3 or +1/3. Electric charge is a fundamental conserved property of some subatomic particles, which determines their electromagnetic interaction. ...


Evidence for the existence of quarks comes from deep inelastic scattering: firing electrons at nuclei to determine the distribution of charge within nucleons (which are baryons). If the charge is uniform, the electric field around the proton should be uniform and the electron should scatter elastically. Low-energy electrons do scatter in this way, but above a particular energy, the protons deflect some electrons through large angles. The recoiling electron has much less energy and a jet of particles is emitted. This inelastic scattering suggests that the charge in the proton is not uniform but split among smaller charged particles: quarks. Deep Inelastic Scattering is the name given to a process used to probe the insides of hadrons (particularly the baryons, such as protons and neutrons), using electrons. ... For other uses, see Electron (disambiguation). ... The nucleus of an atom is the very small dense region, of positive charge, in its centre consisting of nucleons (protons and neutrons). ... In physics a nucleon is a collective name for two baryons: the neutron and the proton. ... In physics, the space surrounding an electric charge or in the presence of a time-varying magnetic field has a property called an electric field. ... A jet is a narrow cone of hadrons and other particles produced by the hadronization of a quark or gluon in a particle physics or heavy ion experiment. ...


Fundamental bosons

Main article: boson

In the Standard Model, vector (spin-1) bosons (gluons, photons, and the W and Z bosons) mediate forces, while the Higgs boson (spin-0) is responsible for particles having intrinsic mass. In particle physics, bosons, named after Satyendra Nath Bose, are particles having integer spin. ... In physics, spin refers to the angular momentum intrinsic to a body, as opposed to orbital angular momentum, which is the motion of its center of mass about an external point. ... In particle physics, gluons are subatomic particles that cause quarks to interact, and are indirectly responsible for the binding of protons and neutrons together in atomic nuclei. ... In modern physics the photon is the elementary particle responsible for electromagnetic phenomena. ... In physics, the W and Z bosons are the elementary particles that mediate the weak nuclear force. ... The Higgs boson is a hypothetical massive scalar elementary particle predicted to exist by the Standard Model of particle physics. ... This article or section is in need of attention from an expert on the subject. ...


Gluons

Main article: gluon

Gluons are the mediators of the strong interaction and carry both colour and anticolour. Although gluons are massless, they are never observed in detectors due to colour confinement; rather, they produce jets of hadrons, similar to single quarks. The first evidence for gluons came from annihilations of electrons and positrons at high energies which sometimes produced three jets — a quark, an antiquark, and a gluon. In particle physics, gluons are subatomic particles that cause quarks to interact, and are indirectly responsible for the binding of protons and neutrons together in atomic nuclei. ... The strong interaction or strong force is today understood to represent the interactions between quarks and gluons as detailed by the theory of quantum chromodynamics (QCD). ... In quantum chromodynamics (QCD), color or color charge refers to a certain property of the subatomic particles called quarks. ... The Compact Muon Solenoid (CMS) is an example of a large particle detector. ... Colour confinement (often just confinement) is the physics phenomenon that color charged particles (such as quarks) cannot be isolated. ... A jet is a narrow cone of hadrons and other particles produced by the hadronization of a quark or gluon in a Particle physics experiment. ... A hadron, in particle physics, is a subatomic particle which experiences the nuclear force. ... For other uses, see Quark (disambiguation). ... The term three jet event, or Mercedes event, refers to particularly distinctive three-jet events found in particle detectors that constitute the most direct evidence currently available for the existence of gluons. ...


Electroweak bosons

Main article: W and Z bosons

There are three weak gauge bosons: W+, W, and Z0; these mediate the weak interaction. The massless photon mediates the electromagnetic interaction. In physics, the W and Z bosons are the elementary particles that mediate the weak nuclear force. ... In physics, the W and Z bosons are the elementary particles that mediate the weak nuclear force. ... The weak interaction (often called the weak force or sometimes the weak nuclear force) is one of the four fundamental interactions of nature. ... In modern physics the photon is the elementary particle responsible for electromagnetic phenomena. ... Electromagnetism is the physics of the electromagnetic field: a field which exerts a force on particles that possess the property of electric charge, and is in turn affected by the presence and motion of those particles. ...


Higgs boson

Main article: Higgs boson

Although the weak and electromagnetic forces appear quite different to us at everyday energies, the two forces are theorized to unify as a single electroweak force at high energies. This prediction was clearly confirmed by measurements of cross-sections for high-energy electron-proton scattering at the HERA collider at DESY. The differences at low energies is a consequence of the high masses of the W and Z bosons, which in turn are a consequence of the Higgs mechanism. Through the process of spontaneous symmetry breaking, the Higgs selects a special direction in electroweak space that causes three electroweak particles to become very heavy (the weak bosons) and one to remain massless (the photon). Although the Higgs mechanism has become an accepted part of the Standard Model, the Higgs boson itself has not yet been observed in detectors. Indirect evidence for the Higgs boson suggests its mass lies below 200-250 GeV.[4] In this case, the LHC experiments will be able to discover this last missing piece of the Standard Model. The Higgs boson is a hypothetical massive scalar elementary particle predicted to exist by the Standard Model of particle physics. ... In physics, the electroweak theory presents a unified description of two of the four fundamental forces of nature: electromagnetism and the weak nuclear force. ... The DESY (Deutsches Elektronen Synchrotron, German Electron Synchrotron) is the biggest German research center for particle physics, with sites in Hamburg and Zeuthen. ... The Higgs mechanism, also called the Higgs-Kibble mechanism or Anderson-Higgs mechanism, was originally proposed in 1964 by Robert Brout and Francois Englert, independently by Gerald Guralnik, Carl Hagen and Tom Kibble, and also by Peter Higgs, following ealier work by Yoichiro Nambu on the structure of the vaccuum. ... Spontaneous symmetry breaking in physics takes place when a system that is symmetric with respect to some symmetry group goes into a vacuum state that is not symmetric. ... The Higgs boson is a hypothetical massive scalar elementary particle predicted to exist by the Standard Model of particle physics. ... The Large Hadron Collider (LHC) is a particle accelerator and collider located at CERN, near Geneva, Switzerland (). Currently under construction, the LHC is scheduled to begin operation in May 2008. ...


Beyond the Standard Model

Although all experimental evidence confirms the predictions of the Standard Model, many physicists find this model to be unsatisfactory due to its many undetermined parameters, many fundamental particles, the non-observation of the Higgs boson and other more theoretical considerations such as the hierarchy problem. There are many speculative theories beyond the Standard Model which attempt to rectify these deficiencies. The Standard Model of Fundamental Particles and Interactions For the Standard Model in Cryptography, see Standard Model (cryptography). ... The Higgs boson is a hypothetical massive scalar elementary particle predicted to exist by the Standard Model of particle physics. ... In theoretical physics, a hierarchy problem occurs when the fundamental parameters (couplings or masses) of some Lagrangian are vastly different (usually larger) than the parameters measured by experiment. ...


Grand unification

One extension of the Standard Model attempts to combine the electroweak interaction with the strong interaction into a single 'grand unified theory' (GUT). Such a force would be spontaneously broken into the three forces by a Higgs-like mechanism. The most dramatic prediction of grand unification is the existence of X and Y bosons, which cause proton decay. However, the non-observation of proton decay at Super-Kamiokande rules out the simplest GUTs, including SU(5) and SO(10). It has been suggested that this article or section be merged into Unified field theory. ... This article or section does not cite its references or sources. ... The strong interaction or strong force is today understood to represent the interactions between quarks and gluons as detailed by the theory of quantum chromodynamics (QCD). ... Spontaneous symmetry breaking in physics takes place when a system that is symmetric with respect to some symmetry group goes into a vacuum state that is not symmetric. ... The Higgs mechanism, also called the Higgs-Kibble mechanism or Anderson-Higgs mechanism, was originally proposed in 1964 by Robert Brout and Francois Englert, independently by Gerald Guralnik, Carl Hagen and Tom Kibble, and also by Peter Higgs, following ealier work by Yoichiro Nambu on the structure of the vaccuum. ... In particle physics, the X and Y bosons are hypothetical elementary particles analogous to the W and Z bosons, but corresponding to a new type of force, such as the forces predicted by grand unified theory. ... In particle physics, proton decay is a hypothetical form of radioactive decay in which the proton decays into lighter subatomic particles, usually a neutral pion and a positron. ... Super-Kamiokande, or Super-K for short, is a neutrino observatory in Japan. ...


Supersymmetry

Main article: supersymmetry

Supersymmetry extends the Standard Model by adding an additional class of symmetries to the Lagrangian. These symmetries exchange fermionic particles with bosonic ones. Such a symmetry predicts the existence of supersymmetric particles, abbreviated as sparticles, which include the sleptons, squarks, neutralinos and charginos. Each particle in the Standard Model would have a superpartner whose spin differs by 1/2 from the ordinary particle. Due to the breaking of supersymmetry, the sparticles are much heavier than their ordinary counterparts; they are so heavy that existing particle colliders would not be powerful enough to produce them. However, some physicists believe that sparticles will be detected when the Large Hadron Collider at CERN begins running. This article or section is in need of attention from an expert on the subject. ... A Lagrangian of a dynamical system, named after Joseph Louis Lagrange, is a function of the dynamical variables and concisely describes the equations of motion of the system. ... In particle physics, fermions are particles with half-integer spin, such as protons and electrons. ... In particle physics, bosons, named after Satyendra Nath Bose, are particles having integer spin. ... Sparticle is a merging of the words supersymmetric and particle. ... In particle physics, a slepton is a hypothetical bosonic partner of a lepton whose existence is implied by supersymmetry. ... In particle physics, a squark is a hypothetical boson partner of a quark whose existence is implied by supersymmetry. ... In particle physics, the neutralino is a hypothetical particle and part of the doubling of the menagerie of particles predicted by supersymmetric theories. ... In particle physics, chargino refers to a charged superpartner, i. ... In physics, spin refers to the angular momentum intrinsic to a body, as opposed to orbital angular momentum, which is the motion of its center of mass about an external point. ... In particle physics, supersymmetry breaking is the process to obtain a seemingly non-supersymmetric physics from a supersymmetric theory which is a necessary step to reconcile supersymmetry with actual experiments. ... A particle accelerator uses electric fields to propel charged particles to great energies. ... The Large Hadron Collider (LHC) is a particle accelerator and collider located at CERN, near Geneva, Switzerland (). Currently under construction, the LHC is scheduled to begin operation in May 2008. ... CERN logo The European Organization for Nuclear Research (French: ), commonly known as CERN (see Naming), pronounced (or in French), is the worlds largest particle physics laboratory, situated just northwest of Geneva on the border between France and Switzerland. ...


String theory

Main article: string theory

String Theory is a theory of physics where all normal matter is comprised of strings (measuring at the Planck length) that exist in an 11 dimensional (according to M-theory, the leading version) universe of the 3 extended space,1 extended time, and 6 extra curled up dimensions. The elementary particles are simply strings vibrating at different frequencies which determines mass,electric charge,strong charge,spin and weak charge.A string can be open (a line) or closed,in a loop (a one dimensional sphere), as a string moves through space it sweeps out something called a world sheet. String theory predicts 1-10 branes (a one brane being a string and a 10 brane being a 10 dimensional object) which prevent tears in the "fabric" of space using the uncertainty principle (eg. the electron orbiting a hydrogen atom is also every where else in the universe). Interaction in the subatomic world: world lines of pointlike particles in the Standard Model or a world sheet swept up by closed strings in string theory String theory is a model of fundamental physics, whose building blocks are one-dimensional extended objects called strings, rather than the zero-dimensional point... M-theory is a solution proposed for the unknown theory of everything which would combine all five superstring theories and 11-dimensional supergravity together. ... This article or section is in need of attention from an expert on the subject. ...


One particular prediction of string theory is the existence of extremely massive counterparts of ordinary particles due to vibrational excitations of the fundamental string. Another important prediction of string theory is the existence of a massless spin-2 particle behaving like the graviton. This article is about the hypothetical particle. ...


Preon theory

Main article: preon

According to preon theory there are one or more orders of particles more fundamental than those (or most of those) found in the Standard Model. The most fundamental of these are normally called preons, which is derived from "pre-quarks". In essence, preon theory tries to do for the Standard Model what the Standard Model did for the particle zoo that came before it. Most models assume that almost everything in the Standard Model can be explained in terms of three to half a dozen more fundamental particles and the rules that govern their interactions. Interest in preons has waned since the simplest models were experimentally ruled out in the 1980s. In particle physics, preons are postulated point-like particles, conceived to be subcomponents of quarks and leptons. ... The Standard Model of Fundamental Particles and Interactions For the Standard Model in Cryptography, see Standard Model (cryptography). ... The Standard Model of Fundamental Particles and Interactions For the Standard Model in Cryptography, see Standard Model (cryptography). ... In particle physics, the term particle zoo is used colloquially to describe a relatively extensive list of the known elementary particles that almost look like hundreds of species in the zoo. ...


See also

Helium atom (schematic) Showing two protons (red), two neutrons (green) and two electrons (yellow). ... This is a list of particles in particle physics, including currently known and hypothetical elementary particles, as well as the composite particles that can be built up from them. ...

References

  1. ^ Gribbin, John (2000). Q is for Quantum - An Encyclopedia of Particle Physics. Simon & Schuster. ISBN 0-684-85578-X. 
  2. ^ Clark, John, E.O. (2004). The Essential Dictionary of Science. Barnes & Noble. ISBN 0-7607-4616-8. 
  3. ^ Veltman, Martinus (2003). Facts and Mysteries in Elementary Particle Physics. World Scientific. ISBN 981-238-149-X. 
  4. ^ Quark experiment predicts heavier Higgs

Greene, Brian (1999). The Elegant Universe. W.W.Norton & Company. ISBN 0-393-05858-1. 

Further reading

Feynman, R.P. & Weinberg, S. (1987). Elementary Particles and the Laws of Physics: The 1986 Dirac Memorial Lectures, New York: Cambridge University Press.


External links


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