The Martlet

As the world’s biggest science experiment powers up near Geneva, UVic particle physicists who contributed to the project’s development are among an international community of researchers preparing to pore over the results.

“There are thousands of the brightest minds on the planet that are attracted to this kind of science,” said Michel Lefebvre, a UVic physics professor. “It is just mind-bogglingly interesting.”

In the last two weeks, scientists at the European Institute for Nuclear Research (CERN) tested the capabilities of the recently active Large Hadron Collider (LHC), a subterranean particle accelerator located near the French-Swiss border.

The LHC is a 27-kilometre circular tunnel that is housed 100 metres underground.

Researchers use special magnets to accelerate two beams, each containing trillions of protons, through the ring.

Moving in opposite directions, the beams collide at high-energy speeds. This collision creates a vacuum, out of which could potentially form new particles, as well some fascinating new insights into the natural laws of the universe.

A machine called the ATLAS detector reads the information produced by the event.

A global community of researchers will analyze the ATLAS data once the project is in full swing. They will look at the events created in the LHC, and search for patterns. If the researchers discover new patterns that are not explained by current theories, they know they’re seeing new physics.

Physicists believe that the accelerator may be the most powerful instrument yet developed for discovering new features of subatomic action.

Lefebvre said these collisions could result in previously-unknown particles, which could be a smoking gun of new physics.

“We’re opening a window where nobody’s looked before,” he said. “This is why it’s so exciting.”

The LHC can be likened to a microscope, said Lefebvre.

A normal optical microscope has three components: a sample, a means of illuminating the sample, and a detector — which is the viewer’s eyes, brain and the microscope’s lenses.

In the case of a normal microscope, the smallest thing anyone can see is limited by the wavelength of optical light, which is approximately half a micron in size. A hair is about two microns thick. To look at anything smaller than that, such as a proton, it is necessary to develop new machines.

This is what scientists have done by creating the LHC.

The difference is that “the sample we’re looking at, it’s not a fly’s wing or a little grain of salt, it’s the vacuum itself, the properties of space-time,” said Lefebvre.

The subatomic dimensions of space-time are nothing new to the UVic Department of Physics, which has been attracting leading minds into its faculty and graduate programs since the 1980s. Currently, the department has the largest faculty of particle physicists in Canada and is involved in multiple experiments internationally.

“Our group here is strong. It’s the strongest in Canada in particle physics,” said Lefebvre.

When Lefebvre became a UVic professor in 1991, he had been working on a collider project at CERN for a number of years.

He brought with him, into the department, research and development for detector technology that was eventually chosen as a component of ATLAS. At that time, the department already contained researchers who had similar expertise from other experiments.

“We all joined forces to start planning, designing, constructing the ATLAS project,” he said.

In the past few years, UVic researchers have built pieces of the ATLAS detector at UVic and at the TRIUMF lab in Vancouver. And, in the 1990s, Lefevbre was part of a $4-million project to build components for ATLAS.

This kind of work is important for science, because there are patterns in physics that can be measured and replicated, even though physicists don’t understand the underlying causes of those phenomena.

An example of this is the different masses of particles. The electron has a mass, the muon has a mass, but the muon is 200 times more massive than the electron.

The reason behind this is still a mystery for physicists, said Lefebvre.

“We have information in front of us, and it’s crying at us, yelling at us, ‘there is something behind this structure, some reason why it is the way it is.’ And we have no clue,” he said.

The work being done at CERN is an attempt to shed some light on this lack of understanding.

“The more we probe nature … the closer we are to understanding how they all fit together,” he said.

One way the CERN team will “probe nature” is by recreating a local condition that existed moments after the beginning of the universe.

The Big Bang theory postulates that the universe began as a small, but very hot, very dense thing. That thing expanded and, as the universe expanded, it cooled.

The energy of two protons colliding at the LHC is about the same amount of energy as a mosquito in flight.

This may not seem like a lot of energy, but all this energy is compacted into a very small volume — the size of two proton beams.

The density of this energy is equivalent to a certain temperature, the same temperature that existed in the universe after a fraction of a second.

“So the Large Hadron Collider is a bit like a time machine,” said Lefebvre. “Not in the sense that you travel in time, but the sense that you probe nature as it was normally in the universe a long time ago.”