World’s Most Powerful Particle Accelerator Set to Launch
This fall, more than 14 years after scientists first broke ground on construction, the multi-billion dollar Large Hadron Collider is expected to send its first beams of protons charging toward one another at near light speeds and then smashing head-on in carefully orchestrated collisions.
The effects are expected to be dramatic. It’s been predicted that the subatomic particles resulting from the crash could mimic conditions that occurred a trillionth of a second after the Big Bang.
Scientists are already powering up the system and preparing to embark on the first series of tests. This week, officials at the European Organization for Nuclear Research (known by its French acronym CERN) announced that on September 10, they will attempt to send proton beams on their first full lap around the circle at a low energy. The higher energy collisions could occur as soon as November.
In nature, particle collisions are constant, and usually involve cosmic rays slamming into the atmosphere.
This machine will smash particles together at slightly under the speed of light, which means they’ll be traveling at faster speeds and higher energies than scientists have ever attempted in a laboratory-controlled setting. Most of the collisions will involve pairs of protons, but in some cases, they’ll also use heavier nuclei, such as neutrons and protons bound together. (A proton is the nucleus of hydrogen, the simplest atom.)
The collisions will occur in a vacuum to prevent interference by other matter.
The project’s goals are simple but lofty: to seek answers to some the most basic questions asked in physics.
“A grand human quest since antiquity has been to understand the basic structure of matter, forces, space and time,” said Steven Giddings, a professor of physics at University of California at Santa Barbara and an expert in the study of black holes. “The LHC is designed to take us in the next step in that quest.”
Some predict that these high-energy collisions could produce never-before-seen particles and possibly a new form of matter, known as the Higgs boson, which may play a major role in the origins of mass. The collisions might also produce dark matter, miniature black holes and possibly even reveal extra dimensions of space.
Gravity is weak compared to other forces. One theory to explain this is that gravity is leaking out into other dimensions of space that humans can’t see — the LHC will test that theory.
Talk of the experiments triggering black holes has led to some sensational newspaper headlines about the collider leading to the end of the planet, but scientists at CERN say it’s not the least bit dangerous.
“I have a wife and three kids,” said Michael Barnett, senior physicist at the Lawrence Berkeley National Laboratory and an education coordinator at CERN. “Do you really imagine if I wasn’t 100 percent convinced, that I would endanger my family? There’s no danger. None.”
This is because black holes would disintegrate into a small spray of particles in about a nano-nano-nano second, Giddings said.
Scientists characterize the mood at CERN as one of busy excitement, anxiety and anticipation. One science writer at CERN has even made a rap video on the project, complete with anonymous dancers and detailed explanations of particle physics (http://www.youtube.com/watch?v=j50ZssEojtM).
“It is as if Mars were enveloped in clouds, and the very first glimpse we get of anything below the clouds is when we land a rover on the surface,” Barnett said. “We are holding our breath in anticipation.”
Giddings points out that without discoveries in fundamental physics, we wouldn’t have cell phones, ipods, computers or CT scans.
“There’s a huge intrinsic benefit in better understanding our place in the cosmos. It’s a basic human drive. The questions we’ve been answering are some of the most basic questions mankind has asked for millennia — along with some new ones.”
When electricity was invented, people had no idea where it would lead — that’s the nature of basic research, Barnett said.
“We like to think that we are re-writing our children’s science textbooks,” he added. “In the same way that Galileo revolutionized our thinking about our place in the universe, we hope our discoveries will give us new insight into mankind’s place in the universe.”