Some questions on strong interaction

[immijimmi]

1. Are quarks created with a specific color charge? For example in pair production a red up quark and a cyan antiup quark?

 

2. Why are there only 8 colour states for gluons? There are nine possible combinations of colour to 'anticolour'.

 

3. If there were only blue and red quarks but no green, would the strong force still have an effect and be able to bind quarks into hadrons?

 

4. Why is the strong nuclear/residual force transmitted by virtual pions, and since that's possible does it mean that all composite particles that have an integer spin (bosonic) can transmit a force in such a manner? (i.e. atoms such as helium 2)

 

If you know the answer to one and not the others just answer that one.

Edited January 5, 2012 by immijimmi

[swansont]

The gluon singlet state is not observed, leaving you with 8.

http://en.wikipedia.org/wiki/Gluon#Color_singlet_states

[immijimmi]

The gluon singlet state is not observed, leaving you with 8.

http://en.wikipedia...._singlet_states

 

So, the gluon singlet state is a 'colourless' gluon? There are 3 of those, though... that means there are only 6 combinations:

 

r /b

r /g

b /r

b /g

g /r

g /b

 

The three that wouldn't be observed are:

 

r /r

b /b

g /g

 

So, why are there 8 observed?

[swansont]

The singlet state is identified in the link I provided — the symmetric superposition of the three color/anticolor pairings.

[Widdekind]

I understand, that the "singlet" gluon amounts, in effect, to an "all white (& anti-white)", i.e. "color-less" gluon, having no forceful effect what-so-ever:

 

[math]g_s \approx g_{\bar{r}r} + g_{\bar{y}y} + g_{\bar{b}b} \approx g_{\bar{W}W} \approx g_{BW}[/math]

Could such a Strong-force "color-less", "black-and-white" gluon be compared, to a Weak-force "neutral current", i.e. [math]Z^0[/math] ??

 

1. Are quarks created with a specific color charge? For example in pair production a red up quark and a cyan antiup quark?

 

I understand, that when gluon bonds "break", they "rip" at the "juncture" between their color & anticolor, creating a new quark & antiquark, having those color & anticolors:

 

[math]g_{\bar{r}r} \rightarrow \bar{q}_{\bar{r}}'q_r'[/math]

I understand, that the new quark & antiquark become bound into new hadrons:

 

[math]q_r : g_{\bar{r}r} : q_y q_b \rightarrow q_r \bar{q}_{\bar{r}}':q_r' q_y q_b \rightarrow q_r\bar{q}_{\bar{r}}'+q_r' q_y q_b[/math]

The resulting meson [math]q_r\bar{q}_{\bar{r}}'[/math], is a pion, which "burps" from one baryon, to a neighboring baryon. The residual Strong nuclear force seems to stem, from the stressing & breaking, of intra-nucleon gluon bonds.

Edited January 13, 2012 by Widdekind

[immijimmi]

The singlet state is identified in the link I provided — the symmetric superposition of the three color/anticolor pairings.

 

Ok, but that still leaves six other observed states and not 8.

 

And, if r /r = colorless, which it does, why do I have to involve b /b and g /g? (as an example)

 

I understand, that the "singlet" gluon amounts, in effect, to an "all white (& anti-white)", i.e. "color-less" gluon, having no forceful effect what-so-ever:

 

[math]g_s \approx g_{\bar{r}r} + g_{\bar{y}y} + g_{\bar{b}b} \approx g_{\bar{W}W} \approx g_{BW}[/math]

Could such a Strong-force "color-less", "black-and-white" gluon be compared, to a Weak-force "neutral current", i.e. [math]Z^0[/math] ??

 

 

 

I understand, that when gluon bonds "break", they "rip" at the "juncture" between their color & anticolor, creating a new quark & antiquark, having those color & anticolors:

 

[math]g_{\bar{r}r} \rightarrow \bar{q}_{\bar{r}}'q_r'[/math]

I understand, that the new quark & antiquark become bound into new hadrons:

 

[math]q_r : g_{\bar{r}r} : q_y q_b \rightarrow q_r \bar{q}_{\bar{r}}':q_r' q_y q_b \rightarrow q_r\bar{q}_{\bar{r}}'+q_r' q_y q_b[/math]

The resulting meson [math]q_r\bar{q}_{\bar{r}}'[/math], is a pion, which "burps" from one baryon, to a neighboring baryon. The residual Strong nuclear force seems to stem, from the stressing & breaking, of intra-nucleon gluon bonds.

 

How is gluon fission relevant to whether quarks have color charge at creation? I mean, sure, you're showing how quarks with c-charge can be created from a gluon, but that already has color charge to pass on. I'm pretty sure that quarks have color charge from creation, but I wasn't sure.

[Widdekind]

I understand, that "color", having three "hues", is mathematically equivalent, to quarks having a "spin S=1 like" property. Perhaps you could conceive of "color" as an "orientation", i.e. xyz, i.e. quarks are "x-oriented", "y-oriented", "z-oriented" ?

 

I understand, that "color" is as intrinsic of a property, as spin, i.e. all quarks must have some "color" state, at all times.