[questionposter]

swansont, on 8 January 2012 - 01:01 AM, said:

No. You will get different quarks or annihilation resulting in other particles. From the interaction standpoint, you need the system to be colorless.

Is it possible to create protons consisting of multiple types of quarks using this meson decay?

[Widdekind]

swansont, on 4 January 2012 - 10:46 AM, said:

The force from color charge does not diminish with distance. At some separation distance you will have added enough energy to just create more quarks.

gluons, carrying "color", can generate more gluons. And, according to "infra-red slavery" -- the inverse of "asymptotic freedom" -- the color-force is weak, at low-frequencies, which I understand to imply "zero force at 'DC' (f=0)". Thus, could you not, in theory, "draw out strings of glue", by super-slowly separating quarks ? As each "string of glue" stretched to its maximum length of a few fm, the gluon(s) would generate another gluon, lengthening the "string". If so, then, in theory, if you stretched quarks apart super-slowly, e.g. over aeons & aeons, you could super-slowly stretch out a "string" of glue, a little like drawing out a fiber of nylon, from its 'soup'.

(In a sci-fi analogy, qualitatively, cp. the quote from Dune, "the slow blade gets through", even when fast strikes encounter hard deflector shields. If you work at super-low frequencies, the quarks barely notice you, only if you try to work quickly does the color force "crack down".)

[swansont]

questionposter, on 8 January 2012 - 05:00 AM, said:

Is it possible to create protons consisting of multiple types of quarks using this meson decay?

I don't think decay would do it, but it might be possible that if three mesons collided you could get two hadrons.

[Widdekind]

According to the Big Bang theory, our universe began in a small, dense, hot state. So, in that early "quark-gluon plasma", the separation distance, between quarks, was small. So, as our universe expanded & cooled, that QGP cooled, "condensing" into "color-less, color-neutral" bound quark groupings, i.e. baryon 'triplets'. Then, as our universe expanded further, those bound quark groupings simply receded from each other, increasingly beyond the reach & range of the Strong 'color' force.

I'm trying to say, that all quarks are bound, into groupings, today, because all quarks became bound, into those groupings, billions of years ago, when our universe was tiny. If our universe had, somehow, begun in a very expanded, diffuse state, similar to present epoch, perhaps then, in theory, you could have isolated quarks, "emanating" attractive Strong force-fields, that simply "couldn't reach" the other quarks, quantum-mechanically huge distances away.

I'm trying to say, that perhaps the observational fact, that all quarks are bound into tight groupings, today, is itself observational support, for the Big Bang theory, i.e. that our universe began, billions of years ago, in a compact state, within which all quarks were well within the range & reach, of other quarks' Strong-force-fields, so that all quarks emerging from the compact state, had already become bound, into tight groupings (and from which no quarks have ever since been 'isolated') ??

[Widdekind]

Particle physics describes

Quote

a dynamical system of coupled gluons... the action includes self-couplings of the gluons. The bare mass-less fields are all charged with respect to each other. The confinement conjecture, is that this input theory, of mass-less charged particles, is unstable to a condensation of the vacuum to a state, in which only massive excitations propagate. In such a state, the gluonic flux, around quarks, should form into the tubes needed for linear confinement (Creutz. Quarks, Gluons and Lattices, p.4).

Does that imply, that, de facto, gluons have mass ?

[swansont]

Widdekind, on 13 January 2012 - 01:00 AM, said:

I'm trying to say, that all quarks are bound, into groupings, today, because all quarks became bound, into those groupings, billions of years ago, when our universe was tiny. If our universe had, somehow, begun in a very expanded, diffuse state, similar to present epoch, perhaps then, in theory, you could have isolated quarks, "emanating" attractive Strong force-fields, that simply "couldn't reach" the other quarks, quantum-mechanically huge distances away.

If physics were different, physics would be different. But this isn't the place to speculate on that.

[questionposter]

Widdekind, on 13 January 2012 - 02:41 PM, said:

Particle physics describes


Does that imply, that, de facto, gluons have mass ?

Massive Excitement=Very Large excitement?

[Widdekind]

swansont, on 13 January 2012 - 04:11 PM, said:

If physics were different, physics would be different. But this isn't the place to speculate on that.

You're denying the Big Bang theory, of a hot dense compact origin, of our universe, from which state, all quarks emerged, bound into color-neutral hadrons ?

[swansont]

Widdekind, on 14 January 2012 - 02:51 AM, said:

You're denying the Big Bang theory, of a hot dense compact origin, of our universe, from which state, all quarks emerged, bound into color-neutral hadrons ?

You'll notice that I quoted "If our universe had, somehow, begun in a very expanded, diffuse state". That's not the Big Bang.

[Widdekind]

swansont, on 14 January 2012 - 09:27 AM, said:

You'll notice that I quoted "If our universe had, somehow, begun in a very expanded, diffuse state". That's not the Big Bang.

Does observed quark color confinement imply the Big Bang, i.e. all quarks began jointly immersed, in a common 'QGP', from out of whose expansion, they all emerged in groups ?

[swansont]

Widdekind, on 14 January 2012 - 11:54 AM, said:

Does observed quark color confinement imply the Big Bang, i.e. all quarks began jointly immersed, in a common 'QGP', from out of whose expansion, they all emerged in groups ?

I have no idea. But, again, the discussion here is not concerning the big bang.

[MigL]

I see what you are getting at Widdekind. The initial conditions of the quark-gluon plasma ( obviously shortly after t=0 ) constrained the quarks to be for-ever-after bound, and that is their state even today and in the future ( assuming no big crunch ).
Your argument that if initial conditions were not hi-energy/density then quarks may not be bound as they are, unfortunately cannot be proven. Still its an interesting hypothesis.

This post has been edited by MigL: 14 January 2012 - 09:35 PM

[Widdekind]

I understand, that the Strong "color" force increases with distance, out to some maximum effective range (~1 fm), and up to some maximum effective strength (~1 GeV/fm = 10tons). I understand, therefore, that "color confinement" presupposes, that the considered quarks, were already quite close to each other, i.e. "all in the same bag" (cp. 'Bag Model'). For such "quarks in a crew", the harder you try to tug on one quark, the harder that quark's colleagues tug back.

But, I also understand, that, out past some maximum effective range (~1 fm), even the Strong "color" force then begins to decline with distance, presumably approximately as 1/d², given that the SF is modeled mathematically as a "gauge field" (Nambu. Quarks).

[immijimmi]

swansont, on 5 January 2012 - 10:36 AM, said:

The interaction between nucleons has a finite range. The interaction between quarks does not drop off. The former is a residual effect of the latter.

http://en.wikipedia....ong_interaction

From the Wiki page:
The strong interaction is observable in two areas: on a larger scale (about 1 to 3 femtometers (fm)), it is the force that binds protons and neutrons together to form the nucleus of an atom. On the smaller scale (less than about 0.8 fm, the radius of a nucleon), it is also the force (carried by gluons) that holds quarks together to form protons, neutrons and other hadron particles.

Strong interaction isn't observed after 3fm, like I said, so we don't know from this information if it has any effect past this distance.

I know i've read somewhere that gluons have mass and was .14 MeV.
Regardless of whether they do or not, there is actually another explanation for the limited range of the color force:
http://en.wikipedia.org/wiki/Gluon
Scroll down to 'confinement' and read.

[immijimmi]

swansont, on 5 January 2012 - 10:36 AM, said:

The interaction between nucleons has a finite range. The interaction between quarks does not drop off. The former is a residual effect of the latter.

http://en.wikipedia....ong_interaction



Any quark you create is bound to at least one other quark. You will never have a single quark.

My apologies, I mistook attributes of the residual strong force as effective on both types.
I have an interesting thought experiment related to this topic, however: In the event that tachyons exist, would a tachyonic quark be able bind with bradyonic quarks into a composite particle if it was to orbit the other quarks at superluminal speeds?

[swansont]

immijimmi, on 23 February 2012 - 09:16 PM, said:

My apologies, I mistook attributes of the residual strong force as effective on both types.
I have an interesting thought experiment related to this topic, however: In the event that tachyons exist, would a tachyonic quark be able bind with bradyonic quarks into a composite particle if it was to orbit the other quarks at superluminal speeds?

That's several layers of conjecture beyond what I could possibly comment on. It presumes that tachyons exist, and would also reflect the same structure as the "normal" particle we already know to exist and also would interact the same way.