Fireworks for the Physicists: A Higgs Is Found

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A picture with a zoom effect show a grafic traces of proton-proton collisions events measured by European Organization for Nuclear Research (CERN) in the Compact Muon Solenoid (CMS) experience on May 25, 2011 in the search for the Higgs boson.

Be grateful America's great historical figures don't talk like scientists. "Mr. Gorbachev, tear down, modify, or otherwise reduce the architectural footprint of this wall," would not have had the same resonance as the original. Patrick Henry would have surely been less memorable if he'd asked for liberty, death or an equitable out-of-court settlement.

This July 4 however belongs to the scientists — at least the ones presiding over a packed press conference in Geneva convened today by CERN, the European Center for Nuclear Research. With cheers echoing and the crowd on its feet, CERN researchers announced that they had nabbed the most sought-after particle in the history of modern physics: the Higgs boson — first theorized nearly 50 years ago — which gives all other particles mass. There's no understating the significance of that: no Higgs, no mass; no mass, no you, me or anything else. Even so, scientist-speak was the rule of the day — at least at first.

"We observe in our data clear signs of a new particle, at the level of 5 sigma, in the mass region of 126 GeV," said Fabiola Gianotti, the head of one of the two main research teams responsible for the findings.

The mass region of 126 GeV means 126 billion electron volts — pretty much a bulls-eye for what the Higgs is supposed to weigh; the level of 5 sigma means how certain the scientists are of their results — and 5 sigma is very, very certain. In Geneva today, that was the stuff of a standing ovation — even as Gianotti hastened to urge patience. "A little more time is needed to prepare these results for publication," she implored.

But never mind the caution.The history-making nature of the moment was undeniable. In the past few years, scientists have been closing in on the Higgs with the physics version of a pincer move — first through experiments at the recently closed Tevatron collider outside of Chicago, and later with CERN's still-new Large Hadron Collider (LHC) on the Swiss-French border. In both places, the nature of the work has been essentially the same: send protons whizzing in opposite directions along massive, oval shaped tunnels until they reach more than 99.999999% the speed of light. When the two swarms of particles collide, they create a shower of smaller, more elementatry particles, mimicking the conditions of the Big Bang. In that shower should be the Higgs.

In the wild — which is to say everywhere in the primordial universe — Higgs bosons would swarm around other elementary particles and confer them mass. The more energetic the elementary particle, the more bosons it would attract and the more massive it would become. The Tevatron had turned up results that pointed to particles in the 115 to 135 GeV range — which strongly suggested a Higgs — and as recently as this week, retrospective analyses of its final runs added to that evidence. But it would be left to the bigger and more precise LHC to seal the deal. And today it did just that.

"It's an incredible thing that it has happened in my lifetime," said Peter Higgs, the 83-year-old Scottish physicist who headed the team that first came up with the theory in 1964 and was in attendance in Geneva today. Other scientists, despite themselves, gave way to a similar measured giddiness. "We have found the missing cornerstone of particle physics," said CERN director Rolf Heuer. "We have reached a milestone in our understanding of nature."

But CERN's work is hardly done. Missing entirely from all of the high-fives and huzzahs today was a single, tiny word: "the" — as in the Higgs boson has been found. The most the scientists were willing to say is that they found a Higgs. The Higgs could come in multiple types and multiple masses and energy levels, and while the discovery settles one question, it opens the door to many more.

"As a layman, I think we did it," said Heuer. "We have a discovery. We have a particle that is consistent with the Higgs boson. [This] opens the way to more detailed studies, requiring larger statistics, which will pin down the particle's properties."

Added CERN research director Sergio Bertolucci: "We stated last year that in 2012 we would either find a new Higgs-like particle or exclude the existence of the Standard Model Higgs. With all the necessary caution, it looks like we are at the branching point. The discovery of this new particle indicates the path for the future."

So CERN will stay busy and the LHC, which cost $10 billion to build, will have more to do before it pays for itself. Make no mistake though: Like the Higgs that comes hidden in a shower of particles, there's a word hidden in the shower of equivocation from Heuer and Bertolucci. That word is a whispered "eureka." The physicists won a very big, very old battle today. So tonight, send up a few fireworks for them; they're surely too modest to do it themselves.