Talk:X and Y bosons

Particle info box

I've added weak_isospin_3 and B-L to the particle infobox {{infobox particle}} but they are not displaying. I thought I'd updated the infobox template, but obviously screwed up somewhere. Could someone have a look? Ta. --Michael C. Price ^talk 09:39, 5 October 2009 (UTC)

The problem seems to be that isospin_3 and B-L appear only in the documentation of the template, but not in the source of the template itself. It's probably the same for some other parameters mentioned in the documentation. --antiXt (talk) 18:22, 5 October 2009 (UTC)

I've fixed the problem. However, "Third component of the weak isospin" seems too verbose; can you come up with something shorter? --antiXt (talk) 18:30, 5 October 2009 (UTC)

Where do you get those weak isospin values? They don't add up right, considering the stated decay modes. They look like they should be X=1 and Y=0. 69.150.232.219 (talk) 02:49, 2 August 2010 (UTC)

You have to watch out for the chirality of the decay products, which are always opposite to each other. Only the left handed particles have I₃. --Michael C. Price ^talk 07:06, 2 August 2010 (UTC)

But haven't we to invert the sequence of the 1st and 3rd Y Boson decay then? Since the Y Boson has a T₃=−1⁄2 and the T₃ of a left handed e⁺ or
d
is +1⁄2, isn't it? But the left handed
u
and
ν
_e have T₃=−1⁄2 and the right handed T₃ of e⁺ or
d
is 0.-- AdAstraPerScientiam ^Talk 20:51, 9 August 2010 (UTC)

I should have said, "Only the left-handed particles, or right-handed anti-particles (= anti-(left-handed particles), have I₃". --Michael C. Price ^talk 09:02, 10 August 2010 (UTC)

Theory

Another question on the theory itself: I played around a bit with the decays and found some others, but haven't found anything in the literature yet about a third boson of type leptoquark. The boson V (to give it any name at all here) would have an electric charge of Q=−2⁄3 and would decay into

V →
d
+
d

V →
u
+
ν
_e

It has a T₃=−1⁄2 and also a B-L = 2⁄3. I haven't detected an error on this. Can someone confirm or discard it? -- AdAstraPerScientiam ^Talk 20:51, 9 August 2010 (UTC)

I removed already →
e⁻
+
d
due to T₃=0 here in the talk page from the V boson. -- AdAstraPerScientiam ^Talk 01:49, 11 August 2010 (UTC)

I think I've probably goofed bigtime on some of the quantum numbers in the side box. Hopefully I can sort it out in a week, if no one else fixes it first.

In the meantime, Two down quarks are not a possible pair of decay products. --Michael C. Price ^talk 13:49, 11 August 2010 (UTC)

Why not? The X Boson decays into two up quarks! I always thought up and down quarks are not so much fundamentally different. -- AdAstraPerScientiam ^Talk 17:28, 12 August 2010 (UTC)

The weak hypercharge of V would be Y_W=−1⁄3. Here it would differ from the X and Y Bosons. But if we combine it with a ^{${\bar {X}}$} or a ^{${\bar {Y}}$} we would get a whole-number Y_W=−2. Or the confinement VXY would have Q=+1 T₃=−1⁄2 and a Y_W=+3 and could decay into a neutron and a proton for example. It's getting more and more beautiful. Some other combined decay examples:

$V{\bar {X}}$ →
e⁻
+ $\Delta ^{-}$

$V{\bar {Y}}$ →
e⁻
+
n

VVX →
n
+
n

-- AdAstraPerScientiam ^Talk 18:38, 12 August 2010 (UTC)

You're starting from the wrong place. To find the allowable decays you have to start from the fundamental multiplet, determine the gauge bosons and then use this to determine all the allowable decays. The SU(5) fundamental multiplet contains 3 coloured right-handed down quarks, the anti-(left handed neutrino) and the anti-(left handed electron). The 3 X-bosons generate the 3 $d$ → ${\bar {e}}$ transitions and The 3 Y-bosons generate the 3 $d$ → ${\bar {\nu }}$ transitions. The other transitions are generated by the standard model gauge bosons (e.g. gluons generate $d$ → $d$). To get a double down decay you would need down and anti-down quarks in the fundamental multiplet.--Michael C. Price ^talk 06:09, 13 August 2010 (UTC)

I see. We are talking about SU(5) solutions and the Georgi–Glashow model (linked in the page) and we are not free here to find any possible solutions. But we have some boundary conditions to fulfill. So we have 24 gauge bosons at all (the 8 gluons of QCD SU(3); the 3 weak bosons: W^+/-, Z⁰ of SU(2); 1 photon for the electromagnetic U(1); and 12 Bosons left for leptoquark interactions: 3 colored X, 3 colored Y and their antiparticles)

and the fermion representations:

(	ν e	d d d )
	e−

(	u u u	u u u , e+ )
	d d d

I think we should take these infos into the Wikipedia article. -- AdAstraPerScientiam ^Talk 14:58, 14 August 2010 (UTC)

AFAIK, the term "X and Y bosons" restricts us to SU(5) - obviously the other theories (all Pati-Salam models?) have new gauge bosons, but I don't what they are called. The technical details you mention should appear in the Georgi–Glashow model article - which is currently incomprehensible to most readers (it is to me). --Michael C. Price ^talk 06:11, 15 August 2010 (UTC)

I think you're right that the term "X and Y bosons" restricts us to SU(5). Of course there's the SO(10) with its fermion representation ^{$\mathbf {16}$} in which both Georgi–Glashow model and Pati-Salam models are embedded. But I'm only in the first phases of understanding here. I know already the representation in SO(10) looks like:

(	u u u	,	ν e	ν e	,	u u u	)
	d d d		e−	e+		d d d

which gives us some more possibilities of transactions (i.e. 45 gauge bosons comprising 30 leptoquarks (5 and their antiparticles times 3 colors), 8 gluons, 3 lefthanded and 3 righthanded weak bosons and the photon). Meanwhile I have to thank you. Already the discussion with you has brought me a great leap forward.-- AdAstraPerScientiam ^Talk 09:16, 15 August 2010 (UTC)

Whilst I think I understand SU(5) I too am in the early stages of understanding SO(10) and the Pati-Salam embedding within it. Here are some collected thoughts on the matter, which might might make a good article one day. I can't find any good didactic sources for Salam-Pati.--Michael C. Price ^talk 12:10, 16 August 2010 (UTC)

Leptoquarks

How about merging Leptoquarks and X and Y bosons just like in german Wikipedia?--Ernsts (talk) 23:12, 1 November 2010 (UTC)

No. Leptoquarks are more general to GUTs, X & Y bosons are specific to SU(5). --Michael C. Price ^talk 01:41, 2 November 2010 (UTC)

incomplete sentence

"Where u is an up quark, d is a down quark, νe is an electron antineutrino and e+ is an positron. Similar decay products exist for the other quark-lepton generations" Bubba73 ^{You talkin' to me?} 03:41, 9 November 2010 (UTC)