TAYLOR BOROWETZ

Grad student Fred Sage works to uncover the secrets of dark matter.

Graduate student Fred Sage’s research goes far beyond the stars.

Sage received his first research project on dark matter from University of Saskatchewan physics professor Rainer Dick during his fourth year of undergraduate studies. He remained under Dick’s guidance to complete his master of science degree and is currently working on his PhD.

Dark matter is exceptionally elusive. It can’t be seen and it reacts extremely weakly with visible matter. Sage said they know that this “invisible space dust” exists because it adds mass to galaxies, bends light and affects the motion of celestial bodies with its gravity.

According to NASA, dark matter makes up over one quarter of the universe while we have only found around five per cent of the universe’s visible matter. All of these dark matter particles are constantly passing through visible matter, including our bodies.

Dick and Sage’s calculations are aimed at finding the probability of a dark matter particle colliding with an atomic nucleus every second.

“We have an idea of what dark matter might be and we’re trying to figure out if that is consistent. If our model — our predictions — fits in with what is observed,” Sage said. The team’s project is plagued with uncertainty in their calculations and inherent difficulties. He said they make mistakes, figure out what went wrong and try again.

Sage, who has been after these mysteries for over five years, searches for the answer alongside Dick, who has been intrigued since the 1990’s.

A clue to advancing their research may have been found in the Higgs boson — an elementary particle that theoretically accounts for the mass of other elementary particles.

“Our model of dark matter relates to normal matter through the Higgs boson, so to understand our model, we have to understand the Higgs boson fairly well and how it interacts with normal matter,” Sage said.

The existence of the particle was confirmed on March 14, providing another foothold; more can be learned about dark matter when scientists can study how atomic nuclei absorb or emit the Higgs boson.

Theoretical calculations like Sage and Dick’s are currently the most efficient way to progress in the field of dark matter.

Since there is no way to examine or manipulate it in a lab, dark matter models cannot be proven or disproven by studying particle collisions. This leaves experimentation many years behind what theorists can accomplish. Physicists like Sage and Dick can mathematically predict the imperceptible results.

“You have this thing, physics — our understanding of how things work­ — and we’re missing pieces here and there. One of those pieces is dark matter. And if we fill that piece in, who knows how it could affect the shape of the rest of the puzzle,” Sage said.

Sage travelled to the 2013 International Conference on the Structure of Baryons in Glasgow, Scotland, to present his findings. Besides sharing what he knew, he had the opportunity to listen to others who were searching for that same puzzle piece.

Even though dark matter may be benign to humans, its effects are profound and far-reaching on the arrangement of space itself. It can help hold entire galaxies together and even aid in their formation.

“It’s very exciting,” Dick said. “To work in a field which can still expand our understanding of the universe in surprising ways and where every generation of scientists knows and understands more than the previous generation.

“Doing undergraduate or graduate research in physics provides an opportunity to be a part of the exciting discovery journey of physics and understanding relativity and quantum mechanics offers incredibly exciting perspectives on the universe,” Dick said. “Even if the mountain is only half scaled, the view is just marvelous.”

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Photo: JordanDumba/Photo Editor