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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 Iaiken on 2/1/2011 6:31:26 PM , Rating: 3
It wasn't long ago until humans could see or detect atoms and the like, even though they're literally everywhere and you're made of them.


The scientists of the Manhattan Project who undertook the great endeavor of splitting the atom were essentially working blind. At the start they didn't even have access to simple computers and everything was done by hand or by slide rule.

Many explanations and ideas regarding fission arose and were discredited. It even took substantial guesswork and elimination to figure out suitable a suitable candidate for fission in U-235. The vast majority of the effort on the project was actually spent on figuring out methods for separating enough U-235 from ores that were primarily composed of the chemically identical U-238 or creating breeder reactors to produce plutonium.

Building the actual bombs was a comparatively trivial engineering problem once they had enough enriched uranium or plutonium for the cores. The gun-type design of "Little Boy" was so simple that they didn't even bother to test it. The amount of enriched uranium was so small at the time, that the idea of testing.

It's amazing what a little imagination, unwavering government support and essentially unlimited resources can achieve.

It's so simple in fact, that in 2004 Joe Biden was presented with a crude-but-functional nuclear device that was built by university students from legally obtainable products. All it needed was a quantity of enriched uranium the size of a softball. This once-great mystery is now so well understood that the abstract processes and even the math behind it is taught most high school chemistry/physics classes.

RE: Wait
By FITCamaro on 2/1/2011 8:41:13 PM , Rating: 2
If I remember correctly, the two bombs dropped on Japan didn't even make all their uranium explode or whatever the term is.

RE: Wait
By jeff834 on 2/2/2011 3:10:02 AM , Rating: 2
React would probably be acceptable.

RE: Wait
By Iaiken on 2/2/2011 9:14:09 AM , Rating: 2
Doesn't matter if the designs didn't work to optimal efficiency. They still instilled so much terror into the population that they went from being militaristic jingos to pacifists almost over night.

RE: Wait
By Iaiken on 2/2/2011 9:23:07 AM , Rating: 2
The amount of enriched uranium was so small at the time, that the idea of testing was seen as a terrible waste of time and resources.


RE: Wait
By UNHchabo on 2/8/2011 1:21:29 PM , Rating: 2
The gun-type design of "Little Boy" was so simple that they didn't even bother to test it.

While you are correct, your wording makes it sound as if Little Boy (dropped on Hiroshima) was the first nuclear bomb to be set off. This is not true:

"Google fired a shot heard 'round the world, and now a second American company has answered the call to defend the rights of the Chinese people." -- Rep. Christopher H. Smith (R-N.J.)
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