Quark Confinement

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darkmatter4brains

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Anybody know what the latest consensus is on the mechanism of Quark Confinement? Or, is this still a mystery of sorts?

Thanks!
d4b
 
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lanceromega

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darkmatter4brains":oq8np88q said:
Anybody know what the latest consensus is on the mechanism of Quark Confinement? Or, is this still a mystery of sorts?

Thanks!
d4b

It Not a mystery, bascially due to Gluons field interactions, the attractive force felt by quarks upon each other grow stronger, not weaker as a function of distants, at a great enought distant the force / energy needed to pull a quark from another quark literally create a quarks and antiquark pair. At this distant the polarization of Vacuum, shield the anti quark created from the other quarks in the particle and it form a bounded state with the removed quark.

so any attempt to remove a quark from a particle like a proton, will create a quark to take its place and the original quark from a pion , a particle that is a quark anti quark combination...
 
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darkmatter4brains

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lanceromega":k85jaf25 said:
darkmatter4brains":k85jaf25 said:
Anybody know what the latest consensus is on the mechanism of Quark Confinement? Or, is this still a mystery of sorts?

Thanks!
d4b

It Not a mystery, bascially due to Gluons field interactions, the attractive force felt by quarks upon each other grow stronger, not weaker as a function of distants

I thought the strong force falls off rapidly with distance .... the energy of which goes like ~ [e^(-mr)]/r
 
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darkmatter4brains

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I don't know why I didn't go to wikipedia in the first place, but here's what I got off there ( similar to what you said ):

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The reasons for quark confinement are somewhat complicated; there is no analytic proof that quantum chromodynamics should be confining, but intuitively, confinement is due to the force-carrying gluons having color charge. As any two electrically-charged particles separate, the electric fields between them diminish quickly, allowing (for example) electrons to become unbound from nuclei. However, as two quarks separate, the gluon fields form narrow tubes (or strings) of color charge, which tend to bring the quarks together as though they were some kind of rubber band. This is quite different in behavior from electrical charge. Because of this behavior, the color force experienced by the quarks in the direction to hold them together, remains constant, regardless of their distance from each other.[citation needed]

The color force between quarks is large, even on a macroscopic scale, being on the order of 100 000 newtons.[citation needed] As discussed above, it is constant, and does not decrease with increasing distance after a certain point has been passed.

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so what the heck is "color force" and how is this different from the regular strong force??
 
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darkmatter4brains

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so, answering my own question again ... more off wikipedia:

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A residual effect of the strong force is called the nuclear force. The nuclear force acts between hadrons, such as nucleons in atomic nuclei. This "residual strong force," acting indirectly, transmits gluons that form part of the virtual pi and rho mesons, which, in turn, transmit the nuclear force between nucleons.

The residual strong force is thus a minor residuum of the strong force which binds quarks together into protons and neutrons. This same force is much weaker between neutrons and protons, because it is mostly neutralized within them, in the same way that electromagnetic forces between neutral atoms (van der Waals forces) are much weaker than the electromagnetic forces that hold the atoms internally together.


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I did not know this about the strong force. Sounds like there is still some mystery to this based on the statement: "The reasons for quark confinement are somewhat complicated; there is no analytic proof that quantum chromodynamics should be confining"

Fascinating ........
 
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MeteorWayne

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Maybe you should have done the research before you posted this thread in Physics :)
 
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darkmatter4brains

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MeteorWayne":zmqa73n4 said:
Maybe you should have done the research before you posted this thread in Physics :)

yeah, but I'm lazy, PLUS, if I did, you wouldn't have had this interesting thread to read. :)

Also, this did lead me to a question that research isn't helping me with ...

I looked through my old QFT textbooks from school and apparently learned this all 10 years ago ... isn't memory a wonderful thing.

What I had highlighted in there from 10 years ago, was this:

In QED, you've got the Feynman diagrams, which basically represent a double series expansion of a path integral. Each higher order term in the double series expansion is represented by a more and more complicated Feynman diagram, with more and more vertices. The sum of all these Feynman diagrams represents the actual physical process. Sounds like the sum would blow up, but it doesn't. That's because each vertex contributes a factor of alpha - the fine structure constant (1/137). So, higher order diagrams start to contribute negligible amounts very quickly.

But in Quantum Chromodynamics, the further out you are (where the mechanism of quark confinement is going to kick in!) the vertexes actually start to contribute more and more. So, the sum DOES blow up here and the Feynman calculus breaks down.

So that's my question: ~10 years ago this was a problem with QCD, there was no real analytical solution for quark confinement, just an intuitive explanation, per the wikipedia article excerpts above.

I'm curious what progress has been made on this. I'm sure something has, but I can't seem to find anything on it. What's the solution to this?
 
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lanceromega

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darkmatter4brains":349eazfw said:
MeteorWayne":349eazfw said:
Maybe you should have done the research before you posted this thread in Physics :)

yeah, but I'm lazy, PLUS, if I did, you wouldn't have had this interesting thread to read. :)

Also, this did lead me to a question that research isn't helping me with ...

I looked through my old QFT textbooks from school and apparently learned this all 10 years ago ... isn't memory a wonderful thing.

What I had highlighted in there from 10 years ago, was this:

In QED, you've got the Feynman diagrams, which basically represent a double series expansion of a path integral. Each higher order term in the double series expansion is represented by a more and more complicated Feynman diagram, with more and more vertices. The sum of all these Feynman diagrams represents the actual physical process. Sounds like the sum would blow up, but it doesn't. That's because each vertex contributes a factor of alpha - the fine structure constant (1/137). So, higher order diagrams start to contribute negligible amounts very quickly.

But in Quantum Chromodynamics, the further out you are (where the mechanism of quark confinement is going to kick in!) the vertexes actually start to contribute more and more. So, the sum DOES blow up here and the Feynman calculus breaks down.

So that's my question: ~10 years ago this was a problem with QCD, there was no real analytical solution for quark confinement, just an intuitive explanation, per the wikipedia article excerpts above.

I'm curious what progress has been made on this. I'm sure something has, but I can't seem to find anything on it. What's the solution to this?

Well alot, first it was the introduct of Gauss Field equation into QCD to show how terms cancel out, this led to the development of lattice QCD calculation that allow scientist to compute the field strength of Gluon quark interactions.

The Color force is the strong force, what binds neutron and proton to each other is Van Waal force, based on gluon quark interaction. Why does the color force increase as in distant is the fact that unlike the electromagnetic force, there are 9 gluons ( actually 8 , two of the gluons identical so we can cancel one out in calculation). The fact is that Gluon can couple to other Gluon, unlike photons that weakly couple to one each other, a Gluon will actually produce addition Gluons to bind to each other, so as gluon interact with Quarks the force of attraction increase at distant. At distant of 10 to -15 meter the Strong force actual polarize the vacuum to a point where new quark pair is created shield any further interaction with original Quark..
 
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darkmatter4brains

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lanceromega":1n6nakg8 said:
darkmatter4brains":1n6nakg8 said:
MeteorWayne":1n6nakg8 said:
Maybe you should have done the research before you posted this thread in Physics :)

yeah, but I'm lazy, PLUS, if I did, you wouldn't have had this interesting thread to read. :)

Also, this did lead me to a question that research isn't helping me with ...

I looked through my old QFT textbooks from school and apparently learned this all 10 years ago ... isn't memory a wonderful thing.

What I had highlighted in there from 10 years ago, was this:

In QED, you've got the Feynman diagrams, which basically represent a double series expansion of a path integral. Each higher order term in the double series expansion is represented by a more and more complicated Feynman diagram, with more and more vertices. The sum of all these Feynman diagrams represents the actual physical process. Sounds like the sum would blow up, but it doesn't. That's because each vertex contributes a factor of alpha - the fine structure constant (1/137). So, higher order diagrams start to contribute negligible amounts very quickly.

But in Quantum Chromodynamics, the further out you are (where the mechanism of quark confinement is going to kick in!) the vertexes actually start to contribute more and more. So, the sum DOES blow up here and the Feynman calculus breaks down.

So that's my question: ~10 years ago this was a problem with QCD, there was no real analytical solution for quark confinement, just an intuitive explanation, per the wikipedia article excerpts above.

I'm curious what progress has been made on this. I'm sure something has, but I can't seem to find anything on it. What's the solution to this?

Well alot, first it was the introduct of Gauss Field equation into QCD to show how terms cancel out, this led to the development of lattice QCD calculation that allow scientist to compute the field strength of Gluon quark interactions.

Thanks. I guess this at least gives me a direction to read more about this. I'd like to see how the math works out - the path integral issue seems like a tricky one to get around. It'll be interesting to see how they did it.
 
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