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abbottsys
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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?
The answer is no for both questions.abbottsys said:Thanks, but I was hoping to get a simple explanation without diving into SU(3) mathematics. For example: each charge has 2 values, and number of charges in the color field =3, so then we have 2^3 = 8. Can this be justified by gauge theory? And does the same formula work for other gauge fields, such as the electroweak field?
abbottsys said:But the formula DOES work for the electroweak field. This field has 2 charges (electric, isospin), so the formula says the number of gauge bosons will be 2^2 = 4 and this is correct (photon, W+, W-, Z). So the formula works for 2 gauge fields: color and electroweak. Simple formulas are always nice ;-)
This is intuitively clear but you always run into trouble how to explain the "minus one". My explanation is not better, it just avoids to talk too much about the "minus one" :-)xepma said:Here's one way to look at it. There are three colors in SU(3) gauge theory. That just means you have three types of charges, usually referred to as red (r), green (g) and blue (b). The gluon carries two charges, meaning there are 3*3 = 9 possible combinations:
rr
gg
bb
rg
rb
etc.
tom.stoer said:This is intuitively clear but you always run into trouble how to explain the "minus one". My explanation is not better, it just avoids to talk too much about the "minus one" :-)
granpa said:like a meson?
abbottsys said: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?
The number 8 corresponds to the number of possible combinations of color charges in the strong force, which is described by quantum chromodynamics (QCD). Gluons are the particles that mediate the strong force, and they themselves carry a color charge. There are 3 possible color charges (red, green, and blue) and their antiparticles, resulting in a total of 6 possible combinations. However, gluons can also have a combination of a color and an anticolor charge, leading to 3 more possibilities. Therefore, there are 8 gluons in total.
In theory, there could be more than 8 gluons if there were more than 3 colors in the strong force. However, current evidence suggests that there are only 3 colors in the strong force and hence only 8 gluons. Additionally, gluons are considered fundamental particles, meaning they cannot be broken down into smaller particles. So, there cannot be less than 8 gluons.
Yes, all gluons have the same mass of 0 and the same charge of 1. This is because gluons are massless particles and have the same color charge. However, they can have different color and anticolor combinations, resulting in different properties such as spin and orientation in space.
Gluons are unique because they have a color charge, which is a property specific to the strong force. This means that they interact with other particles in a different way compared to particles with other charges, such as electric charge. Gluons also have a spin of 1, which is different from other fundamental particles like quarks, which have a spin of 1/2.
No, gluons cannot be observed directly because they are confined within particles that have a color charge, such as quarks. This is due to the nature of the strong force, which prevents single particles with a color charge from existing independently. However, gluons can indirectly be observed through their effects on other particles, such as the production of jets in high-energy particle collisions.