Story of the Biggest Experiment in History Caught on Film
scientists around the world waited with bated breath for the announcement that the long-awaited Higgs boson particle had been discovered. The finding — the result of the biggest and most expensive experiment in history — was set to either confirm reigning models of particle physics, or reveal gaps in scientists' understanding of the universe."I knew this big event was coming, and I wanted it recorded," said producer David Kaplan, a physicist at Johns Hopkins University in Baltimore, Md. "I knew it was going to be extremely dramatic scientifically, and also emotionally, for all of my colleagues," Kaplan told Live Science.
But to understand why scientists need the LHC, one first has to understand the hypotheses it is putting to the test.
Supersymmetry vs. multiverse
An extension of the Standard Model known as supersymmetry suggests a highly structured and symmetrical universe, in which every particle has a supersymmetric twin that has yet to be discovered. Another, somewhat radical hypothesis suggests the known universe is part of a much larger, chaotic multiverse, in which the laws of physics are random.
The film pits Kaplan and Stanford theorist Savas Dimopoulos, proponents of supersymmetry, against the young Princeton theorist Nima Arkani-Hamed, a supporter of the multiverse idea. The LHC offers the chance to test these hypotheses for the first time. If supersymmetry proves itself, physicists are on the right track. On the other hand, "We may fall off a cliff," and find that the fundamental laws of physics turn out to be random, Kaplan said.
Biggest experiment in history
The beam test went off successfully in 2008, but a few weeks later, a catastrophic explosion in the facility vented liquid helium, damaging many of the magnets inside the LHC.
"The whole film changed," said director Mark Levinson, who added he didn't know how long it would take to fix the damage, and whether the film would have a happy ending. Fortunately, repairs were completed, and the collider was up and running by November 2009.
Fast-forward to July 2012, and the discovery of the Higgs. The particle observed by the LHC confirmed what physicists had long suspected, but also brought up new questions.
Most supersymmetry models predict a Higgs boson with a mass of about 115 gigaelectronvolts, or GeV, whereas multiverse models predict a heavier mass of about 140 GeV. The Higgs observed by the LHC was about 125 GeV — smack in the middle, which doesn't confirm or rule out either theory. Instead, it merely narrows down the possibilities.
It's like being lost in the woods, and then getting a hint of the broad direction you should go, Kaplan said, adding, "At least you know which way to start walking."
In the next step, scientists will collide protons at higher energies, to see if even more particles are created, as predicted by supersymmetry. The LHC was shut down for upgrades in 2013, with plans to reopen it running at twice the power in 2015.
The filmmakers hope "Particle Fever" gives audiences an appreciation of particle physics, and gets them excited about learning more. As Kaplan said, "We want people to come out thinking physics is awesome."
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