Thursday, August 6, 2009

The Race For The Secret of The Universe

Physicist Jacobo Konigsberg in front of the collider detector at Fermilab. 
Last September at Fermilab—the legendary physics research facility just outside Chicago —s everal of the nation's top scientists gathered at 1:30 a.m. to hold a somewhat bittersweet all-nighter. They wanted to be together when they, and America, fell behind in what many consider the most important and resonant competition in science: the search for the elusive Higgs boson, also known as "the God particle." 

Physicists believe that this special subatomic particle allows all of the other particles in the universe to have mass and come together to form, well, basically everything that's around us. Without so-called God particles, one Fermilab theorist tells me, "atoms would have no integrity, so there would be no chemical bonding, no stable structures—no liquids or solids—and, of course, no physicists and no reporters." 

Our nation has traditionally been in the vanguard of this kind of physics research, and for years the Tevatron, the 4-mile-round particle accelerator at Fermilab, was the most powerful in the world. That title, however, would be relinquished at 2 a.m. Chicago time, when scientists in Switzerland were scheduled to switch on the Large Hadron Collider (LHC), the new $9 billion, 17-mile-round particle accelerator located near Geneva. Unlike the all-American Tevatron, which is run by the U.S. Department of Energy, the LHC is part of the European Organization for Nuclear 
Research and was funded by an international consortium of 60 countries, including the United States. 

In a Fermilab control room equipped with a satellite link to the LHC, the Americans watched together as science history was made half a world away. Eight days later, there was a very serious accident at the LHC. No one was hurt, but a catastrophic electrical failure led to a section of the underground ring being taken out, and pipes were vaporized by a lightning bolt of escaping energy. Repairing it would take at least a year and tens of millions of dollars. 

Given this reprieve, the physicists at Fermilab began smashing particles as never before—r evving up the Tevatron to more than 2000% of its original capacity and working around the clock. Five months later, in February, they stunned the scientific world by making the first major breakthrough in God-particle research in nearly a decade. They were able to set an upper boundary for its mass, which significantly narrows the search. Armed with this information and the world's best working accelerator, Fermilab researchers now believe, as do some of their frustrated colleagues in Switzerland, that the first sign of the particle could be found on U.S. soil within the coming year. 

"It's challenging but not impossible—and we are crazy enough to up the stakes," says a Fermilab spokesman, Jacobo Konigsberg, a physicist from the University of Florida. "My mother calls me all the time and asks, 'Have you found God yet?'" 

Actually, many physicists cringe at the highly charged nickname "the God particle." They prefer to call it "the Higgs" (after the Scottish theorist who first suggested its existence in 1964). But, whatever its name, all agree that this particular particle could answer the biggest question in science: How did the cosmic crash known as the Big Bang become the universe we live in today?   

To understand the process, researchers have attempted to deconstruct matter into its most basic components. As every high school student can tell you, matter is made up of elements, elements are made up of atoms, and atoms are made up of electrons, protons, and neutrons. In the 1960s and '70s, theorists developed a "standard model" of high-energy physics, which predicted what kind of particles come together to form electrons, protons, and neutrons. Since then, 12 major subatomic particles have been discovered: six uncharged particles called leptons and six charged particles called quarks. Physicists have also identified five particles that carry force, known as bosons. The evasive Higgs is the only boson that has never been observed. And scientists believe that it could contain the very essence—or at least the mechanism—of existence itself, a way to finally understand how matter becomes and remains matter.   

To "see" these particles, protons and anti-protons are smashed into one another in a process that tries to replicate the Big Bang. These crashes take place at Fermilab within long, sealed underground tunnels where electric fields accelerate the particles close to the speed of light. The collisions—imagine a microscopic version of an explosion at a fireworks factory, with rockets shooting in all directions at various angles, arcs, and velocities—are captured by huge banks of ultrasensitive electronic sensors several stories high. 

Two competing research teams are currently at work at Fermilab. Each one has its own football-field-size industrial building and its own sensor array located along the loop of the underground accelerator tunnel. All of the data from the collisions—more than 15 million of them occur per second—are transferred through jungles of thickly bundled colored wires to aisle after aisle of floor-to-ceiling computers. 

The entire process is monitored in two independent control rooms. Standing in the DZero control room, I watch collision after collision on 4-foot-tall monitors. On one screen, colored particles shoot out in different patterns; on another, the same collision is shown as more of a colorful three-dimensional graph. 

The Higgs has been so difficult to find because it decays incredibly quickly—in fireworks terms, it's like a dud rocket without an easily detectable trail. But thanks to the recent discoveries in these control rooms, physicists know better where to look. They're searching for a particle with a mass between 115 and 160 giga-electron volts, which is a little heavier than an atom of silver but lighter than an atom of gold. 

The data gathered today will take weeks to be digested by computers from trillions of collisions to a few thousand of the most intriguing. Those clashes are then analyzed by physicists. "The theory predicts that you'll produce one Higgs every trillion collisions," Konigsberg says. 

Some scientists at Fermilab, including its director, Pier Oddone, believe that they might find more than one Higgs—multiple particles that are responsible for the others having mass. Other researchers wonder what if they proved, instead, that there is no Higgs, which means they'd need to construct an entirely new explanation for how atoms congeal into matter. 

"We're trying to study nature at its most fundamental state and make a connection between the world of the very small and our world," Oddone says. "We're producing particles that have been here since the first trillionth of a second of the universe, but we still don't understand the most basic things." 

To those people who question why this search for matter matters, Oddone notes that along the way, particle-physics research has helped make possible such technologies as the Internet, MRI machines, radiation treatments for cancer, and superconductors. 

Scientists at Fermilab think they'll have until 2011 to be the first to locate the Higgs boson. Although the larger, faster LHC is scheduled to begin powering up in October, it could take a year or more before researchers there gather enough data to find the particle. 

Until then, "we'll scan the hell out of those guys," says Leon Lederman, the lab's 87-year-old genius emeritus, with a mischievous grin. "You know, we have a genetic disease here—c alled optimism."

by Stephen Fried


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