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A visualization of particles jets in the CMS. Yellow is the path of the particles, while blue and red represent energy detected from the particles.  (Source: CERN/Imperial College of London)
Discovery of dark matter's behavior would solve many outstanding mysteries in physics

Dark matter makes up five times more of the universe's mass than visible matter (~25% vs ~5%), yet scientists have yet to directly observe this ultra-abundant substance.  Scientists also have yet to observe dark energy, which may well beat out normal energy in universal abundance.  This lack of direct observations means that scientists know precious little about two of the most important physical components of our universe.

That could soon change.  CERN's Large Hadron Collider, a 17-mile long circular underground track that is chilled to almost zero degrees Kelvin, is recording incredibly violent collisions, the likes of which haven't been seen since billions of years ago.  Those collisions will likely produce exotic substances like dark matter, which will be analyzed by the LHC's instruments, unlocking long debated mysteries of physics.

Scientists think they are making progress in the hunt for the SUSY – also known as supersymmetric particle, or 'sparticle'.  Scientists believe the sparticle may be the mysterious dark matter, given its theoretical stability.

In order to detect sparticles, scientists must probe the matter resulting from the collision for the absence of energy and momenta signals -- the sign that a sparticle was produced, rather than a standard particle.  This lack of energetic emissivity is the reason why dark matter is dark -- it does not transfer energy to photons, like standard particles.

More specifically, the researchers are trying to detect a "jet" of particles traveling in the same direction, post proton-beam collision, that lack a significant amount of detected energy and momentum.  

Professor Oliver Buchmueller [profile], a faculty member at the Department of Physics at Imperial College London who is doing research at CERN, describes the LHC team's findings, stating [press release], "We need a good understanding of the ordinary collisions so that we can recognise the unusual ones when they happen. Such collisions are rare but can be produced by known physics. We examined some 3-trillion proton-proton collisions and found 13 'SUSY-like' ones, around the number that we expected. Although no evidence for sparticles was found, this measurement narrows down the area for the search for dark matter significantly."

The CMS (compact muon solenoid) detector was co-designed by faculty at the Imperial College, one of Europe's best physics schools.  

Professor Geoff Hall [profile], another Imperial College physics faculty member working at CERN, describes the recent detection of "SUSY-like" streams of particles, stating, "We have made an important step forward in the hunt for dark matter, although no discovery has yet been made. These results have come faster than we expected because the LHC and CMS ran better last year than we dared hope and we are now very optimistic about the prospects of pinning down Supersymmetry in the next few years."

Later this year, physicists will run more trials, which they hope will verify the existence of dark matter in the stream.  They also hope that the theory of supersymmetry will be verified as an accurate description of dark matter, allowing the Standard Model of particle physics to be officially extended.

Looking ahead there's also much hope that the higher-energy collisions might yield a legendary Higgs boson, which would offer much more insight into the behavior of the universe.  The LHC's other major detector -- ATLAS (A Toroidal LHC ApparatuS) -- was designed to search for the Higgs boson.

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RE: Wait
By inighthawki on 2/1/2011 10:45:26 PM , Rating: 5
But my point is that you can observe the existence of the matter itself. The touch produces an electromagnetic repulsion, it reflects light, etc. Dark matter cannot be observed (assuming it exists) with current technology. Please don't try to be technical with wordplay.

The fact that you don't interact with it in the same way doesn't mean it isn't there.

I did not say that it didn't, I just said we need to be more open to the idea that it MIGHT not exist. Should we stop looking? No, but we surely shouldn't stop looking into alternatives reasons either.

RE: Wait
By Goty on 2/2/2011 9:35:23 AM , Rating: 2
We can't observe molecular hydrogen in the interstellar medium, either, but we know it's there. You know how we know? We observe its effects on its environment, the same as we observe the effects of dark matter on its environment. The only difference is that we know what types of particles make up molecular hydrogen and we're still trying to figure out what makes up dark matter. We KNOW that "it" exists through observational evidence, we just need to find out what exactly "it" is.

RE: Wait
By JediJeb on 2/2/2011 1:58:45 PM , Rating: 2
Question is how do we know it is dark matter and not just molecular hydrogen that we can not see?

RE: Wait
By Goty on 2/2/2011 3:14:08 PM , Rating: 2
There are other species of gas present in the molecular hydrogen that act as tracers of the molecular hydrogen. There will also always be a small amount of neutral and singly ionized hydrogen present as well that we can detect.

RE: Wait
By inighthawki on 2/2/2011 4:10:53 PM , Rating: 3
But that's the thing, one of your examples exists, we know it exists. The "it" you're referring to, though, may not even exist at all.

Dark matter is just a theory to explain what we observe, it is by no means the end all of possibilities. How do you know that "it" is not simply an unobserved function of gravity, or another unknown force?

Again, I am NOT saying dark matter doesn't exist, just that we should all be open to the possibility that it could also be something else. It just seems a little far fetched to believe that a made up type of invisible matter that makes up the majority of our galaxy (yet we cannot obtain) is the only possible solution to the problem.

RE: Wait
By Goty on 2/2/2011 8:30:09 PM , Rating: 2
Dark matter is the simplest, most likely explanation and it explains a much larger range of phenomena that any form of MOND has ever been able to. The difference is so staggering and dark matter is such an elegant solution, requiring no new physics as far as astronomers are concerned, that, until it can be concretely disproven, it really is the best avenue of progress.

RE: Wait
By kingius on 2/3/2011 11:06:46 AM , Rating: 3

They just went... see that big number we need to put here or the maths just doesn't work? Yes, that. That's ... dark matter. And the other one there? Yes, that big one. That's... dark energy.

It can't be that the maths is wrong. No sir. We can't have just got it wrong. Nope. Dark matter. Dark energy. See? We weren't wrong.

RE: Wait
By tng on 2/3/2011 6:16:33 PM , Rating: 2
until it can be concretely disproven, it really is the best avenue of progress.
Which is why so many of us that stand of the edge of science look in and shake our heads.

New ideas for many mysteries in the world of science are immediately shot down, because they don't match what is already generally accepted, even if the generally accepted idea is far from being proven.

I have heard many scientists go on about how open minded science in general is. Really it is just the opposite from what I have seen.

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