The Biggest, Deepest Questions

The questions don’t get any bigger than the ones probed by faculty and students in Stirling Hall:

• Where do we come from?
• How did the universe evolve?
• What is it made of?
• And why, according to the laws of physics, does the world work the way it does?

Read more on Mauel and Chen in The ongoing neutrino puzzle

These questions led Jennifer Mauel into that circular building on Bader Lane several years ago. Now a fourth-year undergraduate student, Ms. Mauel started her Queen’s degree in Global Development Studies, but early on, she felt a stronger pull to mathematical sciences. She ended up taking a first-year physics course with Professor James Fraser. His teaching impressed her so much that she committed to the field, and has since spent two summers working on the SNO+ experiment in Sudbury with Professor Mark Chen.

"The work is really challenging and fun – we’re doing puzzles all the time,” she says. “These deep, fundamental questions about existence – where we come from, the matter/anti-matter question – there’s nothing more exciting."

Read more on Art McDonald in The neutrino breakthrough

Her thoughts echo a theme that surfaced again and again during interviews with professors, postdocs and students in the Department of Physics, Engineering Physics and Astronomy. The people there are, without a doubt, at the cutting-edge of new discoveries, new technologies, new ideas – with Art McDonald’s Nobel Prize-winning research being the most prominent example to date.

Even if not directly linked to Dr. McDonald’s SNO research, the entire department is riding high on that win – and inspired to keep going, to keep pushing the research forward.

Ms. Mauel and Dr. Chen, through SNO+, are asking the next questions about the nature of neutrinos, trying to understand their mass and why it’s so small.

Read more on Kamaha and Gerbier in The search for dark matter

Gilles Gerbier, Professor and Canada Excellence Research Chair, is also continuing work at SNOLAB – not into neutrinos, but into the nature of the elusive dark matter particle. He is joined in this issue by Alvine Kamaha, postdoctoral fellow, who is building new apparatus to use in the underground lab to find the particles.

“I wanted to be part of something big,” says Dr. Kamaha, who studied in Cameroon and Italy before coming to Queen’s. “When I came here for my PhD, I was blown away – knowing that you can find something that has such a big impact. Dark matter is believed to be 80 per cent of the mass of the universe. Even though we don’t know right now what the application will be when we find it, you know you have contributed to a better understanding of the universe.”

Read more on Courteau and Ouellette in Extra-galactic astronomy

Professor Stéphane Courteau and PhD student Nathalie Ouellette are also on the hunt for dark matter – not underground, but as astronomers, charting the distribution of mass throughout galaxies and clusters of galaxies.

“Just like planets move around the sun due to its mass, stars move within a galaxy due to its total mass – what you can’t see in brightness, is likely dark matter,” explains Ms. Ouellette, now in the final year of her PhD. “I look at how the stars are moving around the galaxy to see how the mass is distributed. I can see how the stars and dark matter play with each other to see how the galaxy is evolving.”

Read more on Singh Mann and Hughes in Light matter/nanophotonics

Moving from dark matter to light matter, we run into Professor Stephen Hughes and PhD student Nishan Singh Mann.

Very much at the theoretical level, they study light matter interactions – the science of optics, and how light interacts with very small structures on the nano-scale. Their research has many applications, from next-generation quantum light sources for quantum computers to biosensors and high-efficiency solar cells.

"These are new nano-quantum technologies of the future that are going to be mainstream in probably 50 years," says Dr. Hughes, who believes that Mr. Singh Mann’s "killer" model – looking at disorder and non-linearities in photonic crystals – is going to have a huge impact across a number of sectors.

Read more on Fraser and Sibley in Laser solutions

Professor James Fraser and master’s student Allison Sibley are also deep into light – particularly laser light and its uses in manufacturing. They are studying lasers used in 3D printing and the challenge of printing in metal, instead of plastic. “What’s going on at the rich and beautiful world at the pinpoint of a laser beam?” says Dr. Fraser.

“Energy is hotter than a volcano down there, so you can imagine the physics going on.” And working at that high temperature (around 1600 C to cut metal), they have to figure out what’s going on very quickly. “I am imaging the actual process while it’s happening so I can detect defects in the parts,” explains Ms. Sibley. “We can change the parameters of the processing laser and correct the defects, stop the process while it’s happening.”

Their hope is that their research into additive manufacturing, building up with metal, instead of subtracting, will contribute to a number of different areas – automotive, aerospace, and transportation in general, where small improvements can yield great results. “If you can make a car 10 per cent lighter, that directly translates into reduced CO₂ emissions. There’s a lot of opportunity,” says Dr. Fraser.

A lot of opportunity, indeed – across the entire department. And while Dr. Fraser says it’s easy to look at the research groups and their unique focus points, it’s also very possible to see the interconnections – particularly how optics and light hit all units – and the overlap between groups.

“Essentially, all of us use light in some way – as a probe and as a tool. And there is also the sheer physical range throughout the groups – from Steve Hughes and the nano-scale to Allison and I on the micro-scale, and off to Stéphane Courteau in the galactic and extragalactic. And then there are the particle astrophysicists – the true experimentalists – who bridge both extremes.”

Reprinted from the Queen’s Alumni Review
By Wanda Praamsma