As soon as the Large Hadron Collider (LHC) revved up its supercooled electromagnets in 2008 -- which promptly "quenched" (read: broke down in a very expensive way) and then restarted the following year -- it's been the one piece of news the world has been eagerly awaiting: confirmation of the discovery of one of the Universe's most secretive particles -- the Higgs boson.
After gazillions of particle collisions and countless rumors of Higgs discoveries, we have... yet another rumor of a Higgs discovery. But this time, the rumor seems to be meatier than ever.
According to PhysicsWorld.com, CERN's Scientific Policy Committee will be meeting on Tuesday (Dec. 13) to discuss, amongst other things, an update on the search for the Higgs boson. Teams from the LHC's ATLAS and CMS experiments will be in attendance.
Interestingly, as noted by the Guardian.co.uk's science correspondent Ian Sample, the head scientists of the two groups will be there to give the Higgs update. "That in itself is telling – usually more junior researchers present updates on the search for the missing particle," Sample pointed out in his Dec. 6 article.
Apart from the heads of ATLAS and CMS being there, why all the excitement?
According to comments left on a number of particle physics blogs, the word is that the LHC is closing in on the Higgs.
The Higgs boson is theorized to be the "force carrier" of the Higgs field -- a field thought to permeate the entire Universe, endowing matter with mass. Only by using powerful particle accelerators like the LHC do we stand a chance of seeing these mysterious particles.
Apparently, both the ATLAS and CMS experiments are independently seeing a Higgs signal, and the predicted mass of the particle agrees with the experimental results. In particle physics-speak, the Higgs appears to have a mass of 125 GeV (gigaelectronvolts).
The upshot is that if this is proven, one of physics' bedrock theories -- the Standard Model -- is holding steady. If the Higgs does exist with this mass, then perhaps some more tricky Universal mysteries can be resolved.
If the insider-trading-like rumors are substantiated, the ATLAS detection has been measured to a 3.5-sigma certainty and the CMS result has been measured to a 2.5-sigma certainty. All these "sigmas" may not mean much, but they are a measure of the statistical certainty of a given result.
In an earlier Discovery News article Sean Carroll, senior research associate in the Department of Physics at Caltech, shed some light on what this means.
"Three-sigma events happen occasionally, especially when you look at a lot of data," he said. "But it could be real."
At 3.5-sigma, the ATLAS measurement has a 0.1 percent chance of being a "random fluke." The 2.5-sigma result has a 1 percent chance of being a fluke. With those odds, it's little wonder there's some excitement stirring. However, particle physicists are meticulous about their statistics before going public with any discovery.
"Three-sigma isn't seen as a 'discovery,' but it would be strong evidence for the existence of the Higgs," said Jon Butterworth, an LHC physicist working with the ATLAS detector. "Really, a 'five-sigma' is classed as a discovery. Five-sigma is the 'Gold Standard.'"
Read more at Discovery News
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