Slashdot Mirror
Large Hadron Collider May Have Produced New Matter
Covalent writes "The Large Hadron Collider, the world's largest and most powerful particle accelerator and the 'Big Bang machine' that was used to discover what appears to be the long-sought Higgs boson particle (as announced July 4), may have another surprise up its sleeve this year: The LHC looks to have produced a new type of matter, according to a new analysis of particle collision data by scientists at MIT and Rice University. The new type of matter, which has yet to be verified, is theorized to be one of two possible forms: Either 'color-glass condensate' — a flattened nucleus transformed into a 'wall' of gluons, which are smaller binding subatomic particles, or it could be 'quark-gluon plasma,' a dense, soup or liquid-like collection of individual particles."
that matters.
As a matter of fact, I am an expert on this topic.
I know its just the heading, but the whole "new matter" vs "new TYPE of matter" is kind of an important distinction.
Imaginary studies done in my head suggest a strong positive correlation between average time-to-comment (TTC) on heavily-scientific Slashdot articles, and the current Wikipedia loading times. Increased delays in Slashdot commenting can be attributed to increased delays in reading the subject's Wikipedia page to amass a sufficient arsenal of technical jargon and basic principles to pass oneself off as an "academic".
Vanity, thy name is Slashdot.
Not really. The current known elementary particles are all neatly arranged into the Standard Model. The one gap (Higgs boson) was recently filled. What we now need is to discover some process which shows the SM to be incomplete.
PlusFive Slashdot reader for Android. Can post comments.
There are two proposed explanations for the signal seen at CMS, and I'm not sure I would describe either as "new." The color glass condensate is basically a nucleus that is flattened into a pancake due to relativistic length contraction in the direction of motion at high energies. This flattening effect spawns large numbers of gluons (the particles that mediate the Strong nuclear force), wich in turn exposes all sorts of interesting effects. The quark-gluon plasma is a state presumed to exist shortly (say, 10 microseconds or less) after the Big Bang, when the universe's energy was packed into an extremely small volume. At high energies and small distances, quarks (the components of hadrons i.e. protons and neutrons) and gluons are thought to separate easily, creating a hot soup of strong force particles. As the QGP expands and cools, it eventually "freezes out" and you get a shower of normal matter particles. This, too, is thought to have happened after the big bang.
Both of these conditions have been observed at the Relativistic Heavy Ion Collider (RHIC) in the USA. The CGC was reported in 2003/2004, and the QGP in 2010/2011. So while observing them at LHC is exciting, neither is really "new." LHC's luminosity is much higher than RHIC's, though, so one would expect to be able to study both conditions more readily...
Let me 'splain. No. There is too much. Let me sum up.
So, when you collide high-energy particles, you get lots of outgoing particles. Sometimes more, sometimes fewer. One thing that you can do to study the outgoing particles is to look at all pairs of tracks in the event (the combinatorics get very large, but you can still do it), and make a histogram of how close together all the pairs were. When you do this, you find that there is a proliferation of tracks that are very close to one another. This is because the outgoing particles tend to come in clusters (we call them "jets"), all moving in approximately the same direction. This happens, more or less, because if you get one outgoing particle with very high energy, but it is an unstable particle, its decay products will tend to be moving in roughly the same direction as the original particle.
Now, you can also do something slightly more sophisticated: instead of just looking at the angle (in any direction) between two tracks, you can use spherical coordinates, and look separately at the angular distance *around* the beamline (azimuth / phi) and the angular distance *from* the beamline (polar angle / theta) (although we actually convert the polar angle into a strange quantity called "pseudorapidity" instead ... this is unimportant for this discussion). When you do that, if you look at events with relatively few outgoing tracks (<35), you see exactly what you expect: an proliferation of tracks that are close in both azimuth and polar angle -- jets again.
On the other hand, if you look at events with lots of outgoing tracks (>= 110), you still see the excess of tracks that are close in both azimuth and polar angle from jets, but you also see a "ridge" -- an excess of tracks that have almost exactly the same azimuth as one another, but have very different polar angles. This is unexpected, and unexpected results == SCIENCE!
So, we expect particles to appear tightly clustered together, but what we see (in some events) is more like a flat spray of particles that goes from one beamline to the other, but is very tightly constrained in one azimuthal slice.
Terrible analogy: We expect cities to occupy a roughly circular area of the earth's surface -- tightly constrained in both latitude (polar angle) and longitude (azimuth). This is like finding a planet that has a city that stretches from pole to pole, but only along a single meridian -- tightly constrained in longitude but totally unconstrained in latitude. It's just plain weird.
SIGSEGV caught, terminating
wait... not that kind of sig.
Our chief weapon is Quarks! And Gluons! Our two chief weapons are Quarks and Gluons! And Plasma! ...
SIGSEGV caught, terminating
wait... not that kind of sig.
We know quite certainly that the standard model is incomplete both from quantum theory and cosmology: If one rejects fine tuning, something has to keep the Higgs mass from diverging due to Top loops. Above a few TeV, something has to keep vector boson scattering cross sections sane. Dark matter and dark energy have to be made of something.
Unfortunately, that it is incomplete is about all the hell we've got at this point. The LHC has basically been ruling proposed SUSY models out unceasingly, and if we're unlucky and New Physics lies past 14TeV, it will likely be a damn long time until we discover it because the LHC took up the theoretical physics budgets of nearly every nation that does theoretical physics for the better part of a decade to build, and they already had the tunnel. To make significant advances with a successor hadron accelerator we'd be talking about building something at least several times larger and the obstacles are enormous... Staggering costs, the irradiation of the inner detectors, data processing, construction times stretching into multiple decades. Not to mention that the LHC consumed most of the world's supply of helium for years on end.
In the worst-case scenario, there's nothing significantly new until one reaches strong-force unification, and that lies a trillion times beyond the LHC,
Why are physicists so eager to show the standard model to be lacking? Every few months now we see articles telling how better experiments are confirming the standard model and eliminating some of the alternatives. Just because the standard model isn't new or built on a spiffy new foundation like "string theory" doesn't mean we should want to kill it. In fact, some of those things probably don't deserve use of the term "theory" since they are more complex and haven't been experimentally confirmed in any way (except to the extent they match the simpler "standard model").
Because the standard model does not work for everything. It dose not work well with what we think we know about general relativity.
The assumption is that the universe does not in fact run on 2 differing sets of rules. So it follows that the standard model wile working very well for the things it works for is not in fact true. Even though we believe it to be false it still works really well so we use it.
The standard model though is not a true representation of how the universe really works. We would like to find that.
Why is it so hard to only have politicians for a few years, then have them go away?
Did it for you: +1 Insightful
Wait... DAMN!
Let me 'splain. No. There is too much. Let me sum up.
We've discovered the Dread Particle Roberts?
That's not true. There are collisions occurring in Earth's atmosphere that dwarf the energies explored by any colliders humans have built. The LHC has been designed for a maximum of 14 TeV. Cosmic rays can have over one million times more energy. That's one reason we're not concerned about the LHC creating a black hole that will swallow the Earth, because it would have happened naturally by now if that had a significant possibility of happening.
What a fool believes, he sees, no wise man has the power to reason away.
To make significant advances with a successor hadron accelerator we'd be talking about building something at least several times larger and the obstacles are enormous... Staggering costs, the irradiation of the inner detectors, data processing, construction times stretching into multiple decades. Not to mention that the LHC consumed most of the world's supply of helium for years on end.
Well we'd best get started then. I can contribute $100 or so and will pick up some helium balloons from the party store. Anyone else in?
Oh enough on this, where is the car analogy guy when you need it?!
Two cars collided head-on and all the debris, blood, fluids, and remains lined up in a 2' wide straight line at a 104 degree angle to the collision. This was not the expected outcome.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
Well, it's just cool because it probes new regions of the parameter space (temperature and density) of quantum chromodynamics (the fundamental theory of the strong nuclear force). Knowing what nuclear matter does under extreme conditions teaches us new things about what kinds of matter that might exist in the cores of neutron stars, whether there could be more compact kinds of stars between neutron stars and black holes and what conditions were like during the first moments after the Big Bang. It also gives us more data to compare against the predictions of quantum chromodynamics, which will help us make sure that that's actually the correct theory of the nuclear forces. I can't think of any practical applications (say, to fission cross-sections or something) off the top of my head, but that doesn't imply they don't exist.
One of the smaller nuclear power plants for a sub might actually be quite efficient for a very large locomotive running on a much larger-than-standard track. At speed with radiator cooling you might manage some good efficiency. Tanker cars for coolant. Green as hell as as far as CO2 is concerned. You could move heavy freight. I bet in the fifties or sixties some serious thought went into big nuclear trains. Not feasible then with the reactors they had, but some of the N power plants in our ships are very compact now I believe. Albeit highly classified. What a poor analogy the poster made in his tirade against the sci fi fan.. Because, obvious security and political disadvantages aside, using a nuclear power plant in a big-ass steam locomotive may not be a half bad idea. Especially these days.
"No fear. No envy. No meanness." Liam Clancy
I think the coolest part is it surprised them, that doesn't happen to often to those guys.
Apocalypse Cancelled, Sorry, No Ticket Refunds