Holes and physics searches
In the children's book "Holes," inmates at the juvenile correction facility called Camp Green are sentenced to spend their days digging holes, looking for treasure buried under a parched desert wasteland. According to legend, somewhere in the desert a treasure is buried. Each day, each inmate is ordered to dig a single deep hole. The hope is that eventually one of the holes will unveil the treasure.
Lots of scientific research has significant commonalities with the book. Scientists who are looking to discover something new about the world sift through their data, trying to find a treasure. While the excitement of possible discovery is what drives them, most of the things they investigate turn out to be dry and empty holes.
While less exhilarating than a discovery, each hole actually represents an advance in our knowledge of the world. After all, scientists now know one more place where the treasure is not. In fact, a plain with a thousand holes represents far more knowledge than the plain before a spade turned over the first shovelful of soil.
One physics idea that is very popular in LHC studies is a subject called supersymmetry. Supersymmetry is thought by some to be the most plausible extension of the Standard Model of particle physics. More than 10,000 papers have been written on the subject.
The principle of supersymmetry has not yet been demonstrated, but countless physics theories incorporate the idea. Scientists have no idea which of these myriad theories might actually represent the truth. Accordingly, they must investigate each theory and see if it is a treasure or just another dry hole.
In today's analysis, CMS physicists studied events containing a photon, a lepton and unobserved energy. Leptons are a class of subatomic particles of which the electron is the most common, and unobserved energy can actually be observed by looking for momentum imbalances in the detector. If scientists found more events with these characteristics than predicted by the Standard Model, it would have heralded a discovery.
Unfortunately for our subatomic treasure hunters, the measurement was perfectly consistent with the Standard Model and, in our literary analogy, was a dry hole. But a dry hole is not a failure. Tomorrow, when they return to their data, they know of one fewer site to dig. And maybe, just maybe, tomorrow's hole will end with the exciting thump of a metaphorical shovel hitting a buried wooden box.
—Don Lincoln
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| These U.S. CMS scientists from Carnegie Mellon University made important contributions to this analysis. |
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