B.C. scientists aim to unlock secrets of the universe
Buried deep beneath the border of France and Switzerland is a machine of such extremes that its properties are difficult to imagine.
When activated later this summer, it will consume as much power as a medium-sized city, operate at temperatures as low as –270 ° C (colder than outer space), and fire a beam of energy powerful enough to melt a small car almost instantaneously.
There is also a chance that when the machine is turned on, it will create miniature black holes that could suck the entire planet into oblivion, though most scientists have dismissed such concerns.
The Large Hadron Collider, as it’s called, is a circular tunnel 27 kilometres long and between 50 and 175 metres underground. Many sections are large enough to fit a cathedral inside with room to spare. Looking at a map of the structure, entire towns appear as nothing more than dots overhead.
For more than a decade, scientists at universities throughout British Columbia have played a significant role in the project. Many of the discoveries these people hope to make with the apparatus are difficult to comprehend. How do you visualize extra dimensions, for example? Or describe so-called dark matter?
These are the types of questions that some 2,000 scientists from almost 50 countries have set out to explore. Their tool is the largest and most powerful particle accelerator ever built, one that will attempt to obtain clues to the origins of the universe by simulating its existence just billionths of a second after the big bang. That's the cosmic explosion theorized to be responsible for the birth of the universe. The European Organization for Nuclear Research (CERN) approved construction outside Geneva in 1994, and Canada made its first financial contribution in 1996. The entire project is estimated to have cost $8 billion.
For the LHC, Canada built a series of large quadruple magnets that can control the direction of a charged subatomic particle with nearly unprecedented accuracy (to within 25 microns). The country’s most significant role, however, was its contribution to something called the ATLAS detector.
The plan for ATLAS is to discover the most basic building blocks of the universe and work to understand the most fundamental forces of nature.
“That was our buy-in,” Nigel Lockyer recently told the Georgia Straight in a telephone interview. Lockyer is the director of TRIUMF, Canada’s national laboratory for particle and nuclear physics, located at UBC. “The Canadian universities got together and decided what part of the experiment they were going to build,” Lockyer said of ATLAS, “and a lot of that was built at TRIUMF.”
Rob McPherson, an associate professor at the University of Victoria and Canada’s representative at CERN, sat down with the Straight at TRIUMF and explained what the Large Hadron Collider will do.
“From this accelerator, we get one proton beam going one way and another proton beam going the other way,” McPherson began. “And then we collide these proton beams in four places, one of which is at ATLAS.” ATLAS was built between 1998 and 2008 by an international collaboration involving more than 2,000 scientists, including over 100 from Canada. It weighs roughly 7,000 tonnes and is the size of a small building.
Protons are positively charged subatomic particles that are a part of what make up the nucleus of an atom. A nucleus is an atom’s very small and very dense centre. When you collide protons at very high energies, they explode and, in the debris, can create new particles.
According to McPherson, the LHC will collide beams of protons (from hydrogen nuclei) travelling at 99.999999 percent of the speed of light. As the beams circle inside the LHC—completing the 27-kilometre circuit 11,000 times per second—their energy will reach unprecedented levels. When two protons collide, 14 trillion electronvolts of energy will be released, which could be enough to produce new types of particles that nobody has ever seen before.
These energies are difficult to relate to everyday life. But McPherson said that the concentrated energy of one beam is roughly that of a 400-tonne train travelling at 150 kilometres per hour—only instead of the energy spread out across the body of an entire vehicle, it exists at a single, very tiny point in space.
Focusing such high energies in such a minuscule space will generate temperatures more than 100,000 times hotter than the heart of the sun, according to a CERN fact sheet.
McPherson went on to explain that ATLAS is one of four detectors that will monitor these collisions, which will re-create conditions similar to those that existed within billionths of a second of the big bang. Experiments at ATLAS will, essentially, take us back in time, close to a point when everything that exists began from an unimaginably small point of infinite energy, when the entire universe was no larger than a sphere one-third of a metre in diameter.
“We don’t know what happens at these scales [of energy],” McPherson said.
Isabel Trigger worked on the ATLAS detector from October 1999 (a few months before she married McPherson) until she was recruited by TRIUMF in June 2005.
Walking through CERN’s European doors is the scientific equivalent of a religious experience, the ATLAS-Canada physics coordinator told the Straight in a telephone interview, although the facility is not the mad-scientist’s project that novelist Dan Brown’s Angels & Demons made it out to be.
“While they do make antihydrogen there, it would take several billion years to make enough to pose a danger to the Earth,” Trigger said. (In Brown’s novel, Vatican City was held hostage by a cult armed with antihydrogen bombs stolen from CERN.) And they are having retina scanners installed for access to the LHC, which Trigger jokingly said “really freaked everyone out”.
Trigger was at CERN working on a component of ATLAS called a muon spectrometer. Muons are elementary particles, among the most fundamental forms of matter.
Rob McPherson, Canada's representative to CERN, and his
wife, TRIUMF’s Isabel Trigger, have dedicated the last
decade to working on the Large Hadron Collider.
ATLAS was designed to measure the direction and energy of elementary particles, partly because that information could hold evidence of something called the Higgs boson particle. The Higgs has never been observed directly because it is highly unstable. It will only exist for one millionth of a billionth of a billionth of a second before decaying into a spray of other particles.
Although widely accepted arguments for the Higgs exist on paper, physical evidence has never been observed. Nicknamed the “God particle”, the Higgs has become something of a Holy Grail for physicists. It could be the Higgs that gives particles (and everything) mass.
And here is where TRIUMF and UBC, UVic, SFU, and other Canadian universities come into play. When the LHC’s beams collide, billions of particle collisions will occur. With all that debris, so much data will make analysis a major challenge.
According to a TRIUMF media release, it is one of only 12 CERN Tier-1 data analysis centres in the world. Every second, 320 megabytes (about 100 songs’ worth) of information will run from ATLAS to these Tier-1 computers via dedicated Internet connections. In this global web of information, the Higgs is one of the first things that scientists will be looking for.
“We have the Standard Model,” Trigger said, which she described as a bunch of equations that explain why particles have mass and interact with forces like electricity and magnetism the way that they do.
Basically, it is a model of the 16 known elementary particles (and their interactions) that make up all matter. But there are some holes in it. Gravity, for one.
Gravity is a function of mass; the greater an object’s mass, the greater its gravitational pull. But the Standard Model cannot account for gravity; it does not explain enough of the mass in the universe.
“There’s no contradiction between gravity and the other stuff we see,” Trigger said, “But we know there’s gravity, and we’d kind of like it to fit the same model.” The Higgs boson would complete the Standard Model. But even the Higgs, a particle that is, theoretically, 100 to 200 times the mass of a proton, cannot be the whole story.
Colin Gay is an associate professor at UBC and a member of the ATLAS-Canada group. He will be working on the central tracking chamber of the ATLAS detector, looking for evidence of physics beyond the Standard Model.
According to Gay, the Higgs is the “bare minimum” scientists working with the LHC can expect to find. Without the Higgs, the Standard Model becomes mathematically nonsensical, he said. “After 30 years, we are finally getting to this crucial energy range where the theory is really backed into a corner.”
But, he continued, “There has to be something else because, really, that model doesn’t make sense to our guts; it doesn’t feel right.” For Gay, the answer to explaining the universe is in something called supersymmetry theory, or even extra dimensions.
It’s a concept that twists the human mind in an unnatural direction.
Gay tried to explain a fourth dimension of space through an analogy: imagine living your whole life on a piece of paper in a world where everything you knew, from the Earth to the farthest reaches of space, existed within that very thin plain. Would you be able to imagine the direction up? No? That doesn’t mean that up is not there.
“It would be a spectacular discovery,” Gay said, “that in addition to the three space dimensions that we have, that there was another one that was fairly large, that we just hadn’t noticed.”
According to Gay, the mass that the Standard Model cannot account for could exist within this extra dimension.
“That would drastically alter our view of how the universe is structured,” he said.
UVic's Rob McPherson, Canada's representative to CERN, on dark matter and supersymmetry.
However, evidence of dark matter and supersymmetry will likely come before any extra dimensions are found, according to UVic’s McPherson.
For decades, McPherson explained in a later interview in his office at TRIUMF, scientists have hypothesized that gravity can be explained by the existence of dark matter in the universe.
But dark matter (along with a mysterious constituent dubbed dark energy) cannot be observed directly and is only assumed to exist because of the movement of galaxies and other very large objects. This is theorized to account for as much as 96 percent of the mass in the observable universe.
“One of the best theoretical models for explaining dark matter is something called supersymmetry,” McPherson said. “In supersymmetry, there is almost always a very good candidate for a massive particle that is almost invisible, exactly what we want for dark matter.”
Supersymmetry theory hypothesizes that every known particle has a partner with an equal mass. The extra mass of these particles could go a long way to accounting for gravity.
ATLAS might be able to detect particles that supersymmetric particles decayed from. This would provide evidence of supersymmetry.
“Additionally, these decays should include dark-matter candidates which show up as missing energy and momentum in our detectors,” McPherson said. “And this would be a fantastically exciting outcome.” It would account for more mass.
Amid all the excitement, some scientists have warned that working with such high energy levels could be catastrophic.
Walter Wagner, a former nuclear safety officer who claims to have been studying nuclear physics for more than 30 years, has brought a lawsuit against the LHC and CERN in a federal court in Hawaii.
According to his complaint, the levels of energy created by the LHC’s collisions could create microscopic black holes or “strangelets”, either of which could destroy the entire planet. A black hole is a region of space with an incredible amount of mass. The result is a gravitational field so powerful that not even light can escape its pull.
Speaking to the Straight from Hawaii, Wagner explained his concerns. “A micro black hole would simply bounce around, hitting other atoms and absorbing them into itself,” he said. Over a period of months or years, a reaction that began in the depths of CERN’s underground laboratories would eventually grow to swallow the Earth.
A strangelet, Wagner continued, is potentially more stable than any kind of existing matter. If one were created inside the LHC, it would convert any matter it came into contact with into a part of itself.
“The larger atom would eventually convert all of the Earth into a large strange atom,” Wagner said.
Part of Wagner’s complaint for a temporary restraining order reads: “There is no question that should defendants inadvertently create a dangerous form of matter”¦or otherwise create unsafe conditions of physics, then the environmental impact would be both local and national in scope, and quite deadly to everyone.”
Wagner maintains that nobody has come up with definite proof that CERN will not create these potentially disastrous particles.
It turns out that he’s technically correct.
Dugan O’Neil is an associate professor at SFU and is one of approximately a dozen scientists that the university will have analyzing data from ATLAS. Federal funding for TRIUMF’s computing centre goes through SFU, making it another Canadian institution that is playing an integral role in CERN’s groundbreaking work.
Addressing concerns raised by Wagner’s lawsuit, O’Neil said that it is never going to be possible to completely exclude some “very strange things” from happening.
“It would be fascinating if those theories were right,” O’Neil, said, only somewhat jokingly. “But the probability that they’re right is exceedingly small.”
He continued, “There’s no evidence that microscopic black holes exist; there’s no evidence that strangelets exist.”
O’Neil said that concerns around micro black holes and strangelets have developed out of mathematical theories written in a particular way that make predictions for these dangerous particles possible. “It’s much easier to come up with a crazy idea than disprove an absolutely crazy idea,” he added.
Asked for odds on whether or not the world will end, O’Neil laughed but declined to commit himself to numbers. “Extremely, extremely unlikely,” he said.
So we could discover how the universe originated, what it is made up of, and why it works the way that it does. And the probability of destroying the Earth in the process is relatively small.
The LHC is estimated to have cost $8 billion, approximately $100 million of which has come from Canada, according to Walter Davidson.
As director of national science facilities for the National Research Council of Canada, Davidson controls the purse strings on the country’s role in the project. Canada has been funding and working on the LHC for 14 years, he said. “Yes, it is expensive, but the financial burden is shared among continents.”
“Why do this and not spend money on poor in Africa? Or a war in Iraq?” Davidson mused. “They are trying to re-create conditions in the Large Hadron Collider that existed in the very, very beginning of the universe, 14 billion years ago.”¦It is part of exploration, part of something deep and innate within humankind to do that.”
For many, this would be enough for Canada’s $100 million. But the country does have more tangible benefits to gain from the LHC. Davidson noted that during the past decade, Canadian industry has been awarded very challenging contracts by CERN.
Canada took on an important role in constructing the LHC and has moved to become a leader in analyzing the data that the LHC will produce, Davidson continued. These accomplishments will likely garner an eventual economic return on Canada’s investment, he said.
The Canadian-designed ATLAS detector–pictured here
nearing completion in 2006–will monitor reactions
involving energy levels never before produced by humans.
CERN has made its share of profitable discoveries (the Internet is a media favourite), but the LHC is not about money. More than two decades ago, Eric Vogt had a dream to expand TRIUMF with a project called KAON. He wanted to build a facility that would then have fired the most intense beam of subatomic particles in the world. As with the LHC, Vogt’s goal was to solve the mysteries of the universe.
In 2009, the construction of Vogt’s dream facility will be completed—but in Japan, not B.C. Vogt was never able to secure the necessary federal funding for his project.
“You win some and you lose some, and we won TRIUMF, after all,” Vogt told the Straight in a telephone interview from his home in Vancouver. “I came here to found TRIUMF in 1965, and that worked.”
From 1981 to 1994, Vogt served as the director of TRIUMF. On May 4, he was celebrated by UBC for four decades of physics teaching and research at the university. For Vogt, answering why the world should spend 14 years and $8 billion on a device with no obvious practical application is beautifully simple.
“One of the most wonderful gifts that we have as human beings is our sense of wonder,” he said. “The fact that we are able to construct some relatively simple pictures using the mathematics that our brains can invent to describe what happens around us”¦that is just a marvellous thing.”
Richard Taylor, recipient of the 1990 Nobel Prize in physics and a professor emeritus at Stanford University, was among the guests at Vogt’s party.
Asked prior to the event why a project such as the LHC is important, Taylor’s answer came quick.
“It’s not important to me; I’m going to die pretty soon.”¦What good is it to my grandchildren? That’s the right question.”
He continued, “I have a mind. I think about things; I’m curious”¦and this is going to tell me some things I don’t know. That’s enough, for me. But for my grandchildren, I want them to start with more knowledge than I started with 50 years ago.”
Taylor said that the LHC will not change peoples’ daily lives any more than Copernicus’s discovery that the Earth revolves around the sun. But although people may not like it or even know it, discovering that humans are not the centre of the universe did change the way the human mind thinks.
So will discovering where our universe came from.