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First Particle Comprising Four Quarks Discovered

Soulskill posted about a year ago | from the odo-is-going-to-be-busy dept.

Science 111

ananyo writes "Physicists have resurrected a particle that may have existed in the first hot moments after the Big Bang. Arcanely called Zc(3900), it is the first confirmed particle made of four quarks, the building blocks of much of the Universe's matter (abstract one, abstract two). Until now, observed particles made of quarks have contained only three quarks (such as protons and neutrons) or two quarks (such as the pions and kaons found in cosmic rays)."

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Yahoo! (5, Funny)

musth (901919) | about a year ago | (#44041443)

I always vowed to open a tall cool one on the day they found a four-quarker.

Re:Yahoo! Pro Lifers!! (-1)

Anonymous Coward | about a year ago | (#44041471)

I always vowed to open a tall cool one on the day they found a four-quarker.

I always vowed to buy a house and decorate it with aborted fetuses. Maybe preserve them with formaldehyde or something.

Re:Yahoo! Pro Lifers!! Score -4 (-1)

Anonymous Coward | about a year ago | (#44042427)

You could use Obama's dog breath and Bless them. You need a few big houses though, lots of aborted people going on.

4.5 litres. Hic. (4, Funny)

Hognoxious (631665) | about a year ago | (#44043587)

Four quarks? That's a Galuon, isn't it?

The Gillette Co. says (5, Funny)

Anonymous Coward | about a year ago | (#44041501)

Fuck everything, we're doing five quarks.

Re:The Gillette Co. says (2, Informative)

stewsters (1406737) | about a year ago | (#44041645)

Re:The Gillette Co. says (1, Informative)

Anonymous Coward | about a year ago | (#44041723)

Yeah, we got it, but thanks for being 'that guy' who's compelled to explain the punchline of a joke.

Re:The Gillette Co. says (1)

93 Escort Wagon (326346) | about a year ago | (#44042027)

I've seen enough people here not get (what I consider to be very) obvious jokes that I don't see the problem.

And most of the time it doesn't appear to be a language or cultural issue either.

Re:The Gillette Co. says (1)

Anonymous Coward | about a year ago | (#44044447)

You're absolutely right... we should always explain the punchlines to jokes just in case someone doesn't 'get it'. We should incorporate it into other media as well. Imagine how much funnier movies/TV/video games etc. would be if they paused after every joke to explain why you should laugh just in case anyone was left out.

Re:The Gillette Co. says (1)

ShanghaiBill (739463) | about a year ago | (#44046697)

I've seen enough people here not get (what I consider to be very) obvious jokes that I don't see the problem.

It is called humor impairment [chicagotribune.com] . It is a common affliction.

Re:The Gillette Co. says (1)

Brucelet (1857158) | about a year ago | (#44041915)

I think I've posted this before in response to that article, but it's amusing that parody of a decade ago is the [cvs.com] reality [amazon.com] of [eshave.com] today [amazon.com] .

Re:The Gillette Co. says (0)

Anonymous Coward | about a year ago | (#44042135)

MAD TV did it first.

feeding obvious troll (1)

Thud457 (234763) | about a year ago | (#44042249)

Mad Magazine
and before that, SNL:
http://boingboing.net/2005/09/14/gillettes-5blade-raz.html [boingboing.net]

Re:feeding obvious troll (1)

azav (469988) | about a year ago | (#44046177)

Ohhh, someone who ready boing boing! Quick Schmedley! Fire up my Friendster and MySpace! I think we may be able to issue a communicaé!

Re:The Gillette Co. says (4, Funny)

Teresita (982888) | about a year ago | (#44041835)

Fuck everything, we're doing five quarks.

And Gillette will get promptly their ass sued by Apple who has already patented the "look and feel" of particles comprised of more than three quarks.

Re:The Gillette Co. says (2)

su5so10 (2542686) | about a year ago | (#44044465)

No way. Apple is a resolutely one-button, one-quark company. Let other companies worry about left quarks, right quarks, middle quarks. up quarks, down quarks...

Re:The Gillette Co. says (-1)

Anonymous Coward | about a year ago | (#44045353)

I think Samsung will to appease their faggot fandroid bitches. I'm sure you'll justify it and cheer them on, little cheerleading faggot cunt.

Re:The Gillette Co. says (1)

EmagGeek (574360) | about a year ago | (#44041843)

Fuck Gillette, we're doing six quarks.

http://www.dorcousa.com/ [dorcousa.com]

Re:The Gillette Co. says (1)

azav (469988) | about a year ago | (#44046181)

That's clearly derivative work son. Patent infringement!

Re:The Gillette Co. says (0)

Anonymous Coward | about a year ago | (#44042177)

Although a joke, should actually be insightful in the end, not funny: Pentaquark [wikipedia.org] .

Re:The Gillette Co. says (1)

toQDuj (806112) | about a year ago | (#44045165)

Indeed, I interviewed a group investigating the pentaquark at SPring-8. This was posted on my blog here: http://www.lookingatnothing.com/?p=366 [lookingatnothing.com]

Re:The Gillette Co. says (1)

UnknowingFool (672806) | about a year ago | (#44042191)

Screw it. Let's go to 11.

Re:The Gillette Co. says (0)

Anonymous Coward | about a year ago | (#44042281)

Funnily enough... http://en.wikipedia.org/wiki/Pentaquark

Pentaquark (2)

Roger W Moore (538166) | about a year ago | (#44042371)

Already been theorised [wikipedia.org] and some experiments claimed to see them a while ago until they fixed their analysis. I'd personally hold out a bit longer before believing in tetraquarks - this is by no means the first claim [wikipedia.org] to observe them and QCD spectroscopy is notoriously hard from both an experimental and theoretical point of view.

Re:Pentaquark (1)

rgbatduke (1231380) | about a year ago | (#44043203)

Aw, now you are being rational. C'mon, when somebody sees a transluminal neutrino, traps a magnetic monopole, measures a signal that might possibly be the long lost Higgs boson, you can't go around doubting it. Where would climate science be if one doubted the spaghetti-snarl output of all of the GCMs and Hansen's predictions of 5 meter SLR by 2100? Where would medicine be if we doubted that oat bran and fish oil pills prevent heart attacks? Where would the Middle East be if all of a sudden all of the Muslims, Christians and Jews suddenly doubted the Bible, Koran, etc, especially the good parts where he promises land to this or that group or gives it permission to enslave or otherwise abuse non-believers?

Next you're going to tell me that "dark matter" might ultimately turn out to be a lot more brown dwarfs than we think there are instead of new physics that enables interstellar transportation. Spoilsport.

rgb

Re:The Gillette Co. says (0)

Anonymous Coward | about a year ago | (#44044881)

They're working on it. A pentaquark [wikipedia.org] makes some sense, theoretically speaking. The basic rule for particles composed of quarks/antiquarks is that they must have a net colour charge - like electric charge, but for the strong nuclear force - which is neutral. Quarks can have colour charges of "red", "green" or "blue", while anti-quarks are "anti-red", "anti-green" or "anti-blue". You can have a neutral colour charge either by having equal amounts of each colour and its anti equivalent, or just by having equal amounts of each colour.

So a pion, for example, consists of two quarks (a normal quark and an antiquark) with colour charges of (say) red and anti-red, so the net charge is neutral. A proton consists of three quarks, with colour charges of red, green and blue, so the its net charge is also neutral. A particle consisting of four quarks might be, for example: red, anti-red, blue, anti-blue. And you can make a five-quark particle with something like: red, green, blue, blue, anti-blue.

Continues to confirm current theories (5, Interesting)

jfdavis668 (1414919) | about a year ago | (#44041513)

It is amazing that these experiments continue to confirm current theories. I was hoping they would find some strange thing that didn't fit, so we could understand why current theories don't explain everything. Maybe next time.

Re:Continues to confirm current theories (1)

M0j0_j0j0 (1250800) | about a year ago | (#44041563)

So someone already knows all this stuff and is just playing the "i told you so" game right!

Re:Continues to confirm current theories (5, Informative)

lgw (121541) | about a year ago | (#44041611)

That's been that state of particle physics for decades. I don't think anyone likes the Standard Model, it's inelegant and has more "elementary" particles than can be easily memorized, but it keeps making accurate predictions. Attempts of think of a simpler model from which one could deduce all the details of the standard model have all failed so far in making better predictions (and in the case of String Theory, turned out to be vastly more complex than what they were trying to simplify).

Re:Continues to confirm current theories (3, Interesting)

QilessQi (2044624) | about a year ago | (#44041771)

Well said. But if the various numbers that make up the SM are axiomatic, it's interesting to consider what the universe might look like if some (or all) of those axioms were changed. Sort of like considering what Euclidean geometry would look like if the parallel postulate were not true, and consequently coming up with spherical and hyperbolic geometry.

After all, there's nothing to say that "other" Universes have to work the same way as ours -- even the mechanics of universe formation might be different.

Re:Continues to confirm current theories (5, Informative)

wonkey_monkey (2592601) | about a year ago | (#44041917)

You might be interested in Greg Egan's Orthogonal [amazon.co.uk] series, set in a universe where time is a space-like dimension. He puts plenty of further reading on his website as well.

Re:Continues to confirm current theories (1)

Charliemopps (1157495) | about a year ago | (#44042199)

Agreed, those books are awesome... and despite the subject matter being ridiculously complex he doesn't go over the top and make it an unintelligible physics lecture. He just surmises how the universe might work and puts a story in the middle of it. One of the more creative works I've ever read.

Re:Continues to confirm current theories (0)

Anonymous Coward | about a year ago | (#44046957)

Does he tirelessly shoehorn in snarky comments about religion and promote his own puerile brand of reddit-atheism in Orthogonal like he does in all his other books?

Re:Continues to confirm current theories (0)

Anonymous Coward | about a year ago | (#44042253)

more "elementary" particles than can be easily memorized

17... and there is a pattern to some of the names. In high school chemistry we had to remember the first 20 elements, in a particular order.

Free parameters not the issue: SM is wrong! (5, Insightful)

Roger W Moore (538166) | about a year ago | (#44042555)

I don't think anyone likes the Standard Model, it's inelegant and has more "elementary" particles than can be easily memorized, but it keeps making accurate predictions.

Actually that is not really true: just about anyone can do a very simple experiment which is inconsistent with the predictions of the Standard Model. Pick up an object and then let it go. There is nothing in the Standard Model which will predict the behaviour you observe. That's why we physicists don't like it. Parts of it are extremely elegant - e.g. the Higgs mechanism - but since it can't explain gravity we know it is wrong and yet we still cannot find any better model that works for all the other fundamental forces and gravity...not to mention explaining other phenomena like Dark Matter, matter/anti-matter asymmetry of the universe, baryon number violation... etc. The number of particles and free parameters is a minor issue!

Re:Free parameters not the issue: SM is wrong! (0)

Anonymous Coward | about a year ago | (#44042847)

I thought gravity was explained by gravitons?
You're definitely right about the other stuff though.

Re:Free parameters not the issue: SM is wrong! (5, Informative)

femtobyte (710429) | about a year ago | (#44042939)

Gravitons are not a Standard Model particle, though you can tack them on to the Standard Model to partially explain some gravitational behavior (though not without introducing mathematical problems). The link between Standard Model (and variants) field theories and General Relativity is still missing: one can calculate how particles act within gravitationally bent spacetime, but there is no "microscopic" model for how particles themselves bend the spacetime around them as you approach high enough energies for that to be relevant.

Re:Free parameters not the issue: SM is wrong! (0)

Anonymous Coward | about a year ago | (#44042867)

That seems a little misleading, considering similar logic would give that the picking up and dropping an object would be inconsistent with Maxwell's equations too. The Standard Model doesn't preclude gravity, and inconsistencies that develop because of gravity and GR are a lot more subtle than just gravity existing.

SM precludes gravity like SR precludes FTL travel (2)

Roger W Moore (538166) | about a year ago | (#44045493)

The Standard Model doesn't preclude gravity

That is like arguing that special relativity does not preclude faster than light travel. You cannot add FTL travel to SR without inconsistencies (like breaking causality) but you technically can add it. You could also imagine developing a framework which expanded on SR and allowed FTL velocities. In the same way adding gravity to the Standard Model creates inconsistencies (renormalization cut-off) but you can imagine a framework which expands on the SM and somehow incorporates gravity.

The only difference between these two is that gravity is a phenomenon that clearly exists whereas FTL does not (as far as we know). Hence we say the SR forbids FTL because we have no way to incorporate FTL and we do not see it. In the same way the SM forbids gravity: it leads to inconsistencies in the theory just like FTL does in SR. However since gravity clearly exists we conclude that the SM is wrong not that gravity is forbidden!

Re:SM precludes gravity like SR precludes FTL trav (0)

Anonymous Coward | about a year ago | (#44046045)

I don't think it is analogous to arguing SR doesn't preclude a mechanism for achieving faster than light speeds. Being able to see gravity exists is a ways away from seeing that gravity is described by GR, which is what the conflict comes down to. I think a more apt, but still contrived analogous situation would be claiming that turning on a flashlight demonstrates SR, but is actually requires a bit more effort to notice that the speed of the light is constant in different frame than just the existence of light. Anyway, not that I am expecting this to be productive to talk about much more.

Re:SM precludes gravity like SR precludes FTL trav (1)

Roger W Moore (538166) | about a year ago | (#44046673)

Being able to see gravity exists is a ways away from seeing that gravity is described by GR, which is what the conflict comes down to.

Eh? I don't know what you were discussing but I was discussing that the SM cannot explain gravity not whether General Relativity accurately describes gravity. Since the SM cannot explain gravity it cannot explain why an object will fall when dropped. Could you bolt some monstrosity onto the SM to explain that one situation? Possibly but I doubt it and, even if you did, what you added would not be gravity.

Re:Free parameters not the issue: SM is wrong! (1)

lgw (121541) | about a year ago | (#44043323)

I've yet to really understand the Higgs mechanism - does it explain why binding energy has/is inertia? I think it would be pretty unsurprising at this point if we one day get a good theory of "more elementary" particles than the standard model, in which all mass is binding energy. Point particle mass seems like the odd exception now. But how do all these different kinds of binding energy each give rise to mass/inertia? Does every field couple to the Higgs field in some way? It just seems very strange.

Re:Free parameters not the issue: SM is wrong! (1)

slew (2918) | about a year ago | (#44045025)

As a non-physicist, my understanding of the Higgs mechanism is pretty weak, but...

The way I understand it the generic idea of the Higgs mechanism isn't simply restricted to be a "mass-generating" mechanism, although the most interesting Higgs mechanism that are searched for are the ones that can suggest electro-weak symmetry breaking which gives non-zero rest masses to W and Z bosons. The reason why most folks are searching for something that can describe this is that W and Z boson have the largest masses (~85x a proton) whereas a simplistic assumption of symmetry in the electric and weak fields would imply that these particles have zero-mass.

The generic Higgs mechanims pre-supposes a field (which exists everywhere there is the effect). Simplistic assumptions of convervation properties of the field manifest themselves as certain symmetries (which imply other symmetries and can be put into a mathematical framework similar to gauge groups, but that's not too important). The question becomes since the classical equations describe a mass-like scalar term that seems to be independent of the gradients and couples to these fields, how can we put a mass-like term into a framework with all these symmetries, yet be have it be non-zero?

The basic idea is that the field must have some sort of symmetry-breaking. At some high-energy (or temperature or potential), the expected value of the mass-like term averages out to zero, but as you go towards low-energy (or temperature, or potential), the expected value becomes non-zero yielding a mass-like term. As it turns out, if the potential of the field is shaped like a W or a sombrero, it can have this property. At high potential (when you can't see the "hat" part), the expection is symmetric around zero and the field has the required symmetry. As the potential goes down (including all the way to zero), the low-energy expectation value falls away from zero (at a consistent radius away from the center because of the "hat"). This is apparently called spontaneous symmetry breaking.

Why would the field potential have this shape? Who knows? But if it does, it can simultaeously satisfy the symmetries and still have a gradient/direction independent expected value term (which would act just like a scalar constant just like mass in all the classical physics formulas).

So what everyone is calling the Higgs field (and higgs particle) are mostly a specific interaction that describes how the W and Z boson can appear to have a non-zero mass-like term with electro-weak symmetry breaking. It is my understanding that it is currently just assumed that all other stuff that has non-zero mass would be similar, but it doesn't really explain what people think of as mass per-se (which has a mysterious gravitational equivalence), it just gives a explanation for the observations that are likely consistent with mass in terms of energy of the various fields (other than gravity).

Re:Free parameters not the issue: SM is wrong! (0)

Anonymous Coward | about a year ago | (#44046165)

dark matter and dark energy are the new aether

Re:Continues to confirm current theories (2)

manu0601 (2221348) | about a year ago | (#44045829)

That's been that state of particle physics for decades. I don't think anyone likes the Standard Model, it's inelegant and has more "elementary" particles than can be easily memorized,

You have poor memory :-)

  • 6 quarks (up, down, charm, strange, top, bottom) and their anti particules
  • 3 leptons (electron, muon, tau), their 3 associated neutrinos, and their anti particules

Re:Continues to confirm current theories (2)

femtobyte (710429) | about a year ago | (#44046125)

Plus the gauge bosons (photon, gluons, W, Z), and the Higgs, which seem to have escaped your memory. Apparently, the Standard Model particles are a bit harder to memorize than you think...

Re:Continues to confirm current theories (1)

manu0601 (2221348) | about a year ago | (#44046437)

Well they did not really escaped my memory and I can add a precision to your precision: the weak interaction bosons are W+, W- and Z.

But are are gauge bosons fundamental particles? They are not used to build compound particles, this is why I did skip them.

Re:Continues to confirm current theories (1)

femtobyte (710429) | about a year ago | (#44046581)

But are are gauge bosons fundamental particles?

Yes, they are considered fundamental/"elementary" by the same logic that the others are: that they are not themselves built of other fundamental particles.

Re:Continues to confirm current theories (0)

Anonymous Coward | about a year ago | (#44046933)

The Standard Model is a relativistic quantum field theory.

The fundamental things in it are not individual quarks, leptons or any other particle, but rather their associated quantum fields.

Particles are just a presentation of excited states of quantum fields; e.g., electrons are the sole field quanta of the electron field which is everywhere in spacetime, or equivalently they are particular excitations of the fermion field which is everywhere in spacetime.

The gauge bosons are excitations of a quantized gauge field, but gauge fields are not real, they are accounting mechanisms that relate observable local symmetries, orientations or states across spacetime intervals too great to be considered local and are what mathematicians would call a connection field. There are connection fields in various relativized QFTs (such as QED, QCD and the Standard Model) and these fields have their own dynamics from self-interaction and in response to interactions with any or all of the fermion fields.

Connection fields are so general that a connection field on spacetime itself is a homeomorphism for the theory of general relativity.

Re:Continues to confirm current theories (1)

Guy Harris (3803) | about a year ago | (#44047003)

The gauge bosons are excitations of a quantized gauge field, but gauge fields are not real

Well, something underlying them must be real in the sense of being able to affect fermions, otherwise my Wi-Fi, radio, and light bulbs wouldn't be working....

Re:Continues to confirm current theories (1)

Dcnjoe60 (682885) | about a year ago | (#44041839)

It is amazing that these experiments continue to confirm current theories. I was hoping they would find some strange thing that didn't fit, so we could understand why current theories don't explain everything. Maybe next time.

It could just be that, particularly when dealing with particle physics, one can only find what one is looking for. Or put differently, you are unlikely to discover something that the theories don't predict, because all of the equipment and tests have been designed to confirm what the theories predict. Of course that is how the scientific method is supposed to work. You come up with a hypothesis, you devise and experiment to test that hypothesis, you repeat it numerous times to confirm the results.

In short, these experiments are designed to confirm existing theories. Now that we know that four quark particles exist, that part is no longer theoretical and new theories can be built on that fact.

Re:Continues to confirm current theories (0)

Anonymous Coward | about a year ago | (#44042103)

The physics is cool, but I'm just excited that someone on the Internet used comprise correctly!

Re:Continues to confirm current theories (3, Funny)

OakDragon (885217) | about a year ago | (#44042257)

The physics is cool, but I'm just excited that someone on the Internet used comprise correctly!

Naturally - they didn't want to comprise their principals!

Re:Continues to confirm current theories (1)

Laxori666 (748529) | about a year ago | (#44043785)

*facepalm* [picardfacepalm.com]

Re:Continues to confirm current theories (1)

Brucelet (1857158) | about a year ago | (#44042109)

I've never quite been comfortable with the idea that we should be disappointed with detailed confirmation of the standard model. Yes there's obviously a more fundamental theory at work that we don't understand yet, but there's no reason that it has to be visible at human-accessible energy scales when the natural (Planck) energy scale of the universe is 16 orders of magnitude larger than the collision energy of the LHC. It's easy to theorize new physics at those energies, but when you don't see anything that shouldn't take away from our wonder at the accuracy of the existing model, which is still behaving nearly flawlessly after almost 50 years.

LOL .... (5, Funny)

gstoddart (321705) | about a year ago | (#44041579)

There ... are ... 4 ... quarks!

And, kidding aside, anyone care to put a meaning for this into layman's terms? Is more quarks == more energetic?

I'm afraid these particles have always been a little too abstract to grok what this means.

Re:LOL .... (2, Informative)

Anonymous Coward | about a year ago | (#44041745)

The layman's answer is that it has no meaning. If you follow the link, it shows a pretty picture about quark arrangements, only the 'Baryonic' section matters at all to a layman, and most baryonic matter still doesn't matter.

For an interested layman, it just means 'these Legos can click together in more ways than we have recorded.'

For any more depth than that, you don't count as a layman anymore, so go read the root papers.

Re:LOL .... (5, Informative)

Anonymous Coward | about a year ago | (#44041931)

anyone care to put a meaning for this into layman's terms?

To my mind the issue is color balance. No, really. Quarks have a property called "color" (not in any way related to visible colors), which needs to be balanced in order to get a stable particle. (It's a consequence of the non-abelian SU(3) gauge group of the strong nuclear force. Aren't you glad you asked?)

The upshot is that to get a stable particle, you need to have a set of blue+anti-blue, or red+anti-red, or green+anti-green, or blue+green+red or anti-blue+anti-green+anti-red quarks. This is the origin of the 2 quark (color+anti-color) or 3 quark (all colors) particle. (Of course, this is a simplification - because of gluons the colors of the particles are constantly swapping around, but in ways that maintain the color balance.)

Having four quarks upsets this notion. You need some way of balancing the color, and the "traditional" ways of doing it won't work. My guess is that this new particle is probably something like a blue+anti-blue+red+anti-red. As the news article mentions, it's apparently still up in the air whether this should really be considered a true four quark particle, or simply two particles (blue+anti-blue & red+anti-red) in very close association.

Re:LOL .... (2)

BitterOak (537666) | about a year ago | (#44042679)

No one is suggesting that this is not a colorless state. It consists, as you suggest, of two quarks and two anti-quarks in a colorless configuration. If it is truly a new state, it should have a different mass than two mesons "stuck together".

Re:LOL .... (2)

SnarfQuest (469614) | about a year ago | (#44042753)

Let's try a car analogy.

Quarks are like cars. When an accident occurs with a Ford Pinto, a Barbie Convertible (with Ken), and a D-9 Cat g and they lock bumpers, they merge and you end up with a Subaru Legacy Outback.

See, quarks can make sense in the real world too! Well, at least as much sense as they normally do.

Re:LOL .... (0)

Anonymous Coward | about a year ago | (#44044105)

I don't understand how you can be so mistaken. There are five quarks. How many do you see now?

Re:LOL .... (1)

su5so10 (2542686) | about a year ago | (#44044509)

Well, first of all, it's two quarks and two anti-quarks. Second, you'll note that that's the same as two mesons glued together (each with one quark and one anti-quark). And as the original article states, there is controversy about whether in fact this is a new type of particle... or just two mesons. "One side proposes that the particle is actually a union of two ordinary particles called mesons .... Other theorists have tentatively labelled the new particle a true tetraquark — four quarks stuck together tightly to form a compact ball. Within the ball, two quarks are bound together, as are two antiquarks." As for the actual number of different quarks, there are actually six (up down strange charm top bottom). Or 18 if you count them by color variant (red-up, blue-up, green-up, etc.).

Re:LOL .... (1)

gstoddart (321705) | about a year ago | (#44045049)

Thank you, I believe I actually followed that.

So if it's a union of two mesons, I'm calling it a mesonicule, but I'm hoping for tetraquark, because that just sounds awesome and makes we want to say "10 quatloos on the newcomer". ;-)

onwards to the pentaquark! (1)

Trepidity (597) | about a year ago | (#44041601)

Can five blades [wikipedia.org] be far behind?

Fractional charges? (1)

Anonymous Coward | about a year ago | (#44041643)

Would particles like this have fractional electrical charges? +4/3, -4/3, etc?

Re:Fractional charges? (0)

Anonymous Coward | about a year ago | (#44041731)

I'm wondering how the hell its color charge works, myself.

Re:Fractional charges? (1)

BitterOak (537666) | about a year ago | (#44041881)

I'm wondering how the hell its color charge works, myself.

As I said in the response to the gp, tetraquarks consist of two quarks and two anti-quarks, the same quark content as two mesons. It is therefore possible for them to be arranged in a colorless state, which is of course demanded by QCD. (eg. a tetraquark could consist of a red quark, a blue quark, a red anti-quark, and a blue anti-quark. Of course, these colors are constantly changing as a result of the gluon field, but the tetraquark will remain overall colorless, just as mesons do.)

Re:Fractional charges? (0)

Anonymous Coward | about a year ago | (#44042229)

Of course after I actually clicked on the article, that made sense. Now I'm wondering how this is different than two mesons "stuck together". Which, according to TFA, it might just turn out to be.

Re:Fractional charges? (1)

BitterOak (537666) | about a year ago | (#44042457)

Of course after I actually clicked on the article, that made sense. Now I'm wondering how this is different than two mesons "stuck together". Which, according to TFA, it might just turn out to be.

Well, the binding energy (which would be reflected in the mass of the particle) would be very different for two mesons stuck together. In a tetraquark, the four quarks would be bound together with essentially the same energy, whereas with two mesons stuck together, there'd be much stronger binding between the two quarks in a meson than between the mesons. But even that would be interesting, as I'm not sure a state with two mesons stuck together have been observed. (Of course, baryons similarly stuck together have been observed: atomic nuclei.)

Re:Fractional charges? (1)

Relic of the Future (118669) | about a year ago | (#44041895)

Anti-quarks have anti-colors.

Re:Fractional charges? (1)

Brucelet (1857158) | about a year ago | (#44041985)

Color charge is easy: anti-quarks have anti-color, so the right combination of quarks and anti-quarks will still balance the color charge of the composite particle. This is well-known in two-quark particles so why wouldn't it work for four?

Re:Fractional charges? (2)

Relic of the Future (118669) | about a year ago | (#44041791)

Two quarks (-1/3 or +2/3) and two anti-quarks (+1/3 or -2/3) so no, sum is always an integer.

Re:Fractional charges? (0)

Anonymous Coward | about a year ago | (#44041795)

No, because they're basically two quark-antiquark pairs.

Fractional particles cannot exist on their own. At least not for any amount of time that would allow us to call them real particles.

Re:Fractional charges? (1)

BitterOak (537666) | about a year ago | (#44041845)

Would particles like this have fractional electrical charges? +4/3, -4/3, etc?

No. The "tetraquarks" that are being talked about in this article consist of a pair of quarks and a pair of antiquarks. (i.e., the same quark content as two mesons). Quarks have charges of +2/3 or -1/3, while anti-quarks have charges of -2/3 or +1/3. Whenever you put together 2 quarks with 2 anti-quarks, you'll always get whole number charges, i.e. -2, -1, 0, 1, or 2. (Try it.)

Langauage drift: "comprise" (-1)

Anonymous Coward | about a year ago | (#44041655)

M-w [merriam-webster.com] claims that sense #3 is "attacked as wrong"; however, in my experience (central Texas), sense #3 is the only one that's considered correct.
If you say "comprising X" instead of "comprised of X" in central Texas, then you should expect to hear "you ain't from 'round here, is ya?"

I find it funny that different regions can have vastly different ideas of which language forms are correct, and that my region is in the minority.

Ferengi? (0)

Anonymous Coward | about a year ago | (#44041729)

ahh.. had a flashback to Quark's bar in Star Trek: Deep Space nine. lol. Apologies to Armin Shimerman. i'm showing my age.

anyways, thanks for posting the link to the interesting article

Re:Ferengi? (1)

OakDragon (885217) | about a year ago | (#44042271)

In DS9, you're just one transporter accident away from having four Quarks.

Clones? On MY garbage scow?! (1)

Thud457 (234763) | about a year ago | (#44042419)

ahh.. had a flashback to Betty and Betty aboard USGP Quark. lol. Apologies to Richard Benjamin. i'm showing my age.

anyways, thanks for posting the irrelevant reminiscence.

Big Bang theory (-1)

Anonymous Coward | about a year ago | (#44041767)

I am not sure we will discover the genesis of the universe. France is the far most advanced country in research around Big Bang. A theory explained here [youtube.com] (read subtitles for those who don't understand French)

Hang on (5, Informative)

newsman220 (1928648) | about a year ago | (#44041777)

When I read the article yesterday they had not confirmed 4 quarks. They suspected four quarks, but it could also be a pair of two-quark particles closely bonded in a hadron molecule. Confirmation was hoped for in a year or so.

Re:Hang on (1)

Xerxes314 (585536) | about a year ago | (#44044749)

There's no real way to "confirm" the number of quarks. Quark number is not a conserved quantum number, so every particle exists as a superposition of different quark numbers. This is particularly problematic if you probe a particle at very high energies; at sufficiently high energies, every hadron (including the humble proton) appears to be a soup of quark-antiquark pairs bubbling out of the vacuum. However, you should be able to make predictions of what the particle's properties will be if it's mostly like a particle that has 4 quarks (really 2 quarks and 2 antiquarks) versus if it's mostly like a particle that is 2 loosely bound mesons (1 quark and 1 antiquark plus 1 quark and 1 antiquark). But there's no definitive way to distinguish between the two.

It's also noteworthy that neither tetraquarks nor mesonic molecules have been previously seen in two experiments. So no matter which it turns out to be mostly like, it's still a discovery.

Re:Hang on (-1)

Anonymous Coward | about a year ago | (#44045391)

Do you pay gay men to come to your home and shit on your face?

Re:Hang on (0)

Anonymous Coward | about a year ago | (#44045905)

Doesn't everyone?

Celebration (1)

Rixel (131146) | about a year ago | (#44041783)

Wow! A quad-quark particle. That must be as exciting for Physicists, as the quad-screwdriver drink I discovered years ago. (or at least I was told I was very happy).

On particle resurrection (1)

K. S. Kyosuke (729550) | about a year ago | (#44041877)

Physicists have resurrected a particle that may have existed in the first hot moments after the Big Bang

I'm pretty certain that these particles do appear every now and then, given how the universe itself acts like a giant particle accelerator - like a much larger, much more powerful, and much much more badass particle accelerator, to be more specific.

Three quarks for Muster Mark! (2)

kstahmer (134975) | about a year ago | (#44041897)

"Three quarks for Muster Mark!
Sure he hasn't got much of a bark
And sure any he has it's all beside the mark."


-- James Joyce, Finnegans Wake [finwake.com]

Four quarks screw up Murray Gell-Mann’s perfect “allusion [takeourword.com] ”.

Re:Three quarks for Muster Mark! (2)

ssam (2723487) | about a year ago | (#44042263)

not really. there are 6 types of quark (plus 6 anti quarks). before we had only observed them bound 2-quark and bound 3-quark states, (though there have been several claimed 5-quark observations that have not stood up). Now we have 2 groups claiming to see a 4-quark state

I don't care (1)

TheSkepticalOptimist (898384) | about a year ago | (#44042021)

As long as my car still gets 40 rods to the hogshead then that's the way I likes it.

Re:I don't care (1)

JustOK (667959) | about a year ago | (#44043729)

pffft, I have a Zc(2900) in my garage.

So, Four Quarks and a Penny? (1)

erroneus (253617) | about a year ago | (#44042023)

...still don't know her last name...

There are (1)

Prince Vegeta SSJ4 (718736) | about a year ago | (#44042247)

How many quarks do you see? There....Are.....Four.......Quarks......

Why does this make me think of..... (1)

3seas (184403) | about a year ago | (#44042659)

...Deep Space Nine?

Missed Naming Opportunity (0)

Anonymous Coward | about a year ago | (#44042887)

quad quarks or just QQ

they keep changing this (1)

slashmydots (2189826) | about a year ago | (#44045941)

Seriously, they keep changing this since I was in high school and I'm only freaking 25. Last I heard, protons and neutrons were each made up of 3 quarks, not were quarks themselves. What gives?

Re:they keep changing this (0)

Anonymous Coward | about a year ago | (#44046023)

Last I heard, protons and neutrons were each made up of 3 quarks, not were quarks themselves.

They still are made of three quarks in a basic sense.

What gives?

Your reading comprehension?

Let me name this particle: (-1)

Anonymous Coward | about a year ago | (#44046241)

The Quarter Pounder with Cheese. It is also really unstable as it quickly disappears from any stationary state, decays to murky colored forms and becomes the stuff where new particles grow.

Where's the science? (0)

Anonymous Coward | about a year ago | (#44046423)

The articles are behind paywalls, so this article provides nothing of value.

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