What is Gluons: Definition and 67 Discussions

A gluon () is an elementary particle that acts as the exchange particle (or gauge boson) for the strong force between quarks. It is analogous to the exchange of photons in the electromagnetic force between two charged particles. In layman's terms, they "glue" quarks together, forming hadrons such as protons and neutrons.
In technical terms, gluons are vector gauge bosons that mediate strong interactions of quarks in quantum chromodynamics (QCD). Gluons themselves carry the color charge of the strong interaction. This is unlike the photon, which mediates the electromagnetic interaction but lacks an electric charge. Gluons therefore participate in the strong interaction in addition to mediating it, making QCD significantly harder to analyze than quantum electrodynamics (QED).

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  1. ohwilleke

    I Glueballs Observed For The First Time

    One of the first particles predicted by quantum chromodynamics (QCD), which consists of the laws of physics related to the strong force, whose properties have been calculated for almost fifty years, is the glueball. The glueball is a strong force bound composite particle made up of gluons, but...
  2. casparov

    A Can Non-Commutative Geometry Describe Gluons?

    Hey, I have a question regarding the gluons. Is it possible for a non-commutative group/geometry to represent them mathematically ? Replacing the Gell-Mann matrices. I read that the frameworks for gluons /gluonic forces are various, depending on the context.
  3. Cody Livengood

    B Do Alternative Explanations for Gluons Exist and How Can We Test Them?

    I understand how the existence of quarks is inferred from the three particle-emitting cones or jets and by the quarks’ ability to deflect particles passing through the composite particle, but I don’t see how the existence of gluons is conclusively demonstrated by this rather than just being an...
  4. ohwilleke

    I Has photoproduction of gluons been observed?

    I am wondering if a process with an initial state of two photons leading to an end state with two (or more) gluons has been observed. I have seen some papers (like this one) that seem to suggest that this is the case, but none of them say so as clearly as I would like to be confident that this...
  5. R

    B Electrons, quarks and gluons made from something or nothing?

    Most articles said electrons, quarks and gluons are indivisible thus have no compositions unlike the other particles. So, does that means electrons, quarks and gluons are composed of nothing and these elementary particles are indeed 100% void?
  6. R

    I Gluons and Their Charge: Exploring Interacting Bosons with Spin 1

    hello, i am thinking about gluons (Spin = 1) or gluons like particles. We know they harve charges (color,anticolor) for example red,antigreen and so on. My question now is do exist interacting bosons for this charges? Must they have Spin 2?
  7. S

    B Why Photon & Gluon are Exceptions from Higgs Field

    The photon and the gluon in the Standard Model do not interact with the Higgs field and are hence massless and travel at the speed of light. Is there a simple explanation why these two elementary particles are the exceptions?
  8. A

    I Question about gluons and nucleon binding

    The strong force is mediated by gluons which bind quarks together to make protons and neutrons but extends some distance outside the proton, neutron particle boundary and is said to hold nucleons together to form the nucleus. proton electrostatic charge and the electrostatic force tries to push...
  9. Q

    B Exploring Gluon Interaction for Matter Creation

    Just trying to get to the bottom of a thought. If glouns interact with each other or itself, could there be a multiple glouns orbiting each other? Could this orbit create acceleration, and mass, and create quarks? Or possibly more gluon mass?
  10. K

    I Understanding the W Decay Branching Ratio to Quarks & Gluons

    Hello! In Modern Particle Physics by Mark Thomson, in the Electroweak Unification chapter, pg. 412 he talks about the branching ration of the W decay to quarks. And for this he includes both the ##W\to q \bar{q'}## and ##W\to q \bar{q'}g## i.e. the state with a gluon and 2 quarks in the final...
  11. F

    I Does Lattice QCD use virtual gluons?

    I'm given to understand that perturbation methods don't work in QCD because the coupling constant is too large. So they use supercomputers to calculate equations at various points on a lattice. Does this lattice method still take into account the virtual gluons that we might see in perturbation...
  12. F

    I Gluons: Particles or Not? Evidence for their Particle Nature

    What evidence is there that gluons are even particles? They were originally proposed to supply an extra quantum number to comply with the Pauli exclusion principle. So gluons are supposed to carry a color-anticolor charge in order that the quarks in baryons would add up to the color white. But...
  13. Paul Colby

    I Gluon creation and annihilation operators

    Hi, When one quantizes EM the resulting gauge boson, the photon, ends up being its own antiparticle. From what I read of gluons, they have anti particles. I can follow how anti particles come about quantizing a complex-valued field like that for electrons. For the spin 1/2 case non-interacting...
  14. ohwilleke

    B How many gluons on average are there in a proton at once?

    A proton is made of quarks and gluons bound by the strong force in a confined system. Further, all protons are basically interchangeable parts for the purposes of this question. Each one is identical in all material respects. Scientists know a lot about gluon energy density in protons. We have...
  15. Spinnor

    B Branes, gluons, time reversal, and string theory.

    So a gluon in string theory may be an open string whose ends live on one or two branes? These strings have an orientation along the string? Does the orientation change direction if we reverse time, some where I thought I read that one can think of a flow along the string so if you reverse...
  16. Sophrosyne

    I Why are gluons considered to be elementary particles?

    Gluons are often depicted as fundamental particles in the Standard Model. But in looking at their mechanism, it seems they are not really fundamental particles in the sense that they are fundamental, indivisible, building blocks. They are mesons- a composite quark-antiquark pair, where their...
  17. K

    B Since gluons are massless, shouldn't glueballs also be massl

    since gluons are massless, shouldn't glueballs also be massless? is there any possibility gluons acquire mas by interacting with other gluons, not higgs?
  18. D

    Why can't there be other Boson particle clusters

    I most recently heard about the new mathematics that help predict glueballs properties better. I had the really strange question of, why can't all other bosons have a cluster particle, like the glueball. Is it due to there force strength over distance or am I missing something.
  19. Dounia

    Do We Observe Gluons Experimentally?

    Do we observe the gluons experimentally? or they are just virtual bosons ?
  20. Dounia

    Gluons Massless? Explaining Short-Range Strong Force

    how to explain the fact that the gluons are massless, whereas the strong force is short range ?
  21. DaniV

    Gluon Wavelength in Nucleons & Barions

    The Gluones qualities are similler to the photones by the fact that both of them have a state mass of zero and dual wave-particle behavior.. My question is what the range of the wavelengthes of the Gluons in the nucleons and in another barions?
  22. J

    How are the quarks in a proton or neutron held together?

    I've been trying to find a source for this somewhere, but I always end up with different sources explaining what holds protons and neutrons together in the nucleus of an atom. I know that the gluons hold them together, but I'm not sure exactly how they do this, and what type of transfers occur...
  23. Alex299792458

    What are the 8 flavors of gluons?

    Everywhere I see on a standard model it say's that there are 8 flavors of gluons. What do the flavors mean and are the 8 flavors?
  24. OdysseasTS

    Schools Beamline for schools, Greek Delegation

    Hey! So I found this ( http://home.web.cern.ch/about/updates/2014/11/beamline-schools-competition-2015-launches-today ) and my high school's physics teachers liked the concept! So I've created a team to participate in this years contest. We were thinking to do something relevant with antimatter...
  25. llynne

    Gluons, where do they come from and where do they go?

    I want to learn more about gluons. I understand that they are what bind the neutrons and protons into a nucleus. Do they spontaneously arise from a neutron+ positron relationship or are they related to some process?
  26. Physicist50

    Can Individual Gluons Be Extracted from a Nucleus?

    I was wondering if it was possible to extract individual gluons from a nucleus, and if so, how?
  27. T

    The Mystery of 8 Gluons: Uncovering the Secrets of Particle Physics

    I've only read some popular science books on particle physics so my understanding is pretty basic. There are three colors and three anticolors. 3 x 3 will give us 9 gluons. Subtracting the red-antired and the other two leaves us with 6 gluons. Those science books only explain...
  28. V

    Soft gluons and colinear gluons

    Is there a difference between soft and colinear gluons? Are soft gluons the ones with small energy, or with small PT with respect to the qqbar axe (in this case soft and colinear would have the same meaning)?
  29. W

    Understanding Quarks, Anti-Quarks, and Gluons: A Confused WilliamJ's Inquiry

    I have been learning some stuff off of youtube, but I did not get a full enough understanding of how quarks have colors, and anti-quarks have anti-colors and how the gluons have to be colors and anti-colors and how it all works. Some of it doesn't make any sense. The first question is about a...
  30. B

    What are the differences between photons and gluons?

    It is said in particle data sheets that photons and gluons both have 0 mass, 0 electric charge, and a spin of 1. If the two particles both have the same properties, then how is it possible to tell the difference between them? Can a complete table of properties comparing the photon with the gluon...
  31. B

    Why do gluons and W and Z bosons have a limited range?

    Why do the gluon and W and Z boson particles have a limited range of movement, 10-15m for the gluon and 10-18m for the W and Z bosons, when the photon particles, gravitational force, and other particles have no limit to the distance they can travel?
  32. P

    Soft and ultrasoft gluons in QCD

    I'm reading about factorization in QCD. The terms "soft gluons" and "ultrasoft gluons" are frequently referred to. I know how they are defined in terms of power counting, but don't understand their physical significance. In which QCD processes are soft gluons important, and in which are...
  33. Vorde

    Six Superheavy Gluons: Fact or Fiction?

    I read some time ago in a book on physics (I believe it was A Brief History of Time, but I can't be sure) that mentioned how the current model for particle physics had the 16 particles of the standard model, plus six superheavy gluons that are far too massive to ever be witnessed. Am I...
  34. jal

    How many gluons are there in a proton?

    How many gluons are there in a proton? http://upload.wikimedia.org/wikipedia/commons/9/92/Quark_structure_proton.svg http://en.wikipedia.org/wiki/Proton Protons are spin-½ fermions and are composed of three quarks,[3] making them baryons (a sub-type of hadrons). The two up quarks and one...
  35. A

    Exploring the Mysterious 8 Gluons

    8 Gluons...? I am studying quarks again, and the gluons that are exchanged, and I really want to learn about WHY ARE THERE ONLY 8 GLUONS? This has been puzzling me so I was wondering if somebody could help me! Thanks.
  36. Spinnor

    Are the gluons that make up a proton considered virtual particles?

    Are the gluons that make up a proton or neutron considered virtual particles? Thanks for your help!
  37. M

    Exploring the Reality of Gluons: Debunking Misconceptions in the Standard Model

    I have been told that the gluon, unlike the photon, is an artefact of the mathematical technique used (perturbation theory), and that the only massless particle in the standard model is the photon. Is this true?
  38. A

    Why are there 8 gluons in the color force?

    Why are there exactly 8 gluons? Is this related to the fact that the color force has 3 charges, and if so how? More generally, is there a simple formula that gives the number of gauge bosons for any gauge field?
  39. G

    Gluons relating to quantum chromodynamics

    I know gluons relating to quantum chromodynamics are the force that holds quarks or whole nuclei of the atom together, is it considered a particle, or since its a force,is it just representing something invisible, is it actually there, like quarks or protons and neutrons. The same with all bosons.
  40. R

    QCD Calculation for e+e- Annihilation: Quarks, Gluons, & Hadrons

    In e+e- annihilation, are the jets that are produced quarks and gluons, or hadrons? What is the basic idea behind a QCD calculation for such a process? For example, do I take the two initial states to be e+e-, and the two final states to be q+q- (quark and antiquark), but also add the...
  41. T

    Exploring the Binding Energy and Gluons: What Holds Nucleons Together?

    What actually holds nucleons together? Is it gluons from quarks (ie the strong force), or the mass defecit in total nucleon mass (binding energy)? How does one differentiate between these? Regards in advance
  42. H

    Source of Soft Gluons: Questions & Answers

    When two high energy nuclei collide with each other, the hard and soft gluons "hidden" in their wavefunctions are freed. Then the produced system of the hard gluons begins to interact with the system of the soft gluons. Sometimes the system of the soft gluons is called the low energy...
  43. R

    What are the eigenvalues of the color isospin for gluons and quarks?

    seems like a basic question and I'm sure many would answer that these are all "spin-1" particles...but that's not their "isospin", right? can someone in the know please straighten things out.
  44. G

    Does the Detection of Gluons Provide Strong Evidence for Their Existence?

    Hi to everyone: Does anybody of you know when was the gluon detected?, and how do you detect gluons? I hope you can answer Thank you
  45. U

    How do gluons bind quarks together?

    How does the exchange of gluons between quarks "bind" them together?
  46. F

    Understanding gluons and SU(3)

    How are gluons related to the generators of SU(3), the Gell-Mann matrices? I do not understand how the structure constants f and d describe how, for example, a red-antigreen gluon transforms into a red-antiblue and a blue-antigreen one. Do the f or the d factors describe the three-gluon...
  47. C

    What distinguishes different gluons?

    What distinguishes different gluons? All 8 have spin 1 and zero mass so what properties make a gluon different from any other?
  48. F

    Determining Min. Charge States of Yukawa's Particle & Why Gluons are Massless

    Hi, i am kind stuck on this question as i don't know what equation to use. doesn't seem to be in any books. By considering possible interactions between protons and neutrons, determine the minimum number of charge states of yukawa's particle. Also why is the interquark force of finite...