This week's announcement of Canadian Dr. Arthur McDonald's Nobel Prize in Physics for his work on neutrinos is a great boost for Canadian science. But should we care about mysterious particles that seem to have nothing to do with daily life?

You bet we should.

While it is true that billions of neutrinos are passing through your head at this very moment, they will not affect your brain, alter the results of the election, or make you change your vacation plans. In fact, neutrinos have almost nothing to do with life on Earth, because they don't "see" the Earth. They pass right through our entire planet like sunlight passing through a pane of glass. They don't see us, and we barely see them.

So why should we care about them?

Neutrinos are part of the invisible universe, which, it turns out, makes up more of the universe than what we actually see in telescopes.

When you look into the night sky, the moon, planets and stars are only a small part of what is actually out there. The blackness between the stars is really what most of the universe is made of. Hidden in the black are elusive neutrinos, mysterious dark matter particles and equally mysterious dark energy. 

Nobel Prize Arthur McDonald Physics Kingston Ont Oct 6 2015

Arthur McDonald, a professor emeritus at Queen's University, is a co-winner of the 2015 Nobel Prize in Physics for his work on tiny particles known as neutrinos. (Fred Chartrand/Canadian Press)

Together, these invisible particles and forms of energy make up 95 per cent of the universe.

In other words, the stuff that we are made of — ordinary matter — is only 5 per cent of reality. So, we still have a lot to learn about the fundamental nature of the universe and all the forces that hold it together. Our ignorance far exceeds our knowledge.

But studying that invisible universe is difficult because, well, we can't see it.

That's why Canada, along with collaborators in countries around the world, are building exotic devices, such as the Sudbury Neutrino Observatory and the Super Kamiokande Detector in Japan, to try to capture these ethereal particles to understand what the universe is actually made of.

Dr. McDonald's work, along with that of colleagues in Japan, showed how neutrinos that are produced in the sun change their identity when traveling to the Earth, and that they have mass.

This solved a long-standing mystery about the amount of energy coming from the sun, which, before this work, fell short of theoretical models. It turns out that some of the sun's energy is being carried away by neutrinos that we couldn't find because they were hiding on us by changing their clothes.

So, the answer to a simple question a child might ask — "What makes the sun shine?" — has been answered.

But there's more to it than that. This type of basic research is important, because grasping the forces that power the sun, and run the universe on a large scale, could become relevant here on the ground in the future.


This map shows the layout of the Sudbury Neutrino Observatory (SNOLAB) from above and below ground.

Efforts are already under way to harness the same type of energy produced in the centre of the sun, in nuclear fusion reactors that could provide clean energy in the future.

Studies of the unusual, dualistic behaviour of subatomic particles has also  opened up the new field of quantum computing, which could result in the fastest, most powerful computers ever built.

Does that mean we will one day be able to use beams of neutrinos to provide straight-line communication, right through the Earth? Perhaps. Who knows what can come from understanding the fundamental forces of nature?

We've come a long way since the days when we thought the Earth was flat, but we are still largely in the dark when it comes to knowing about the universe and our place in it. That makes the work of Dr. Arthur McDonald a shining light beaming into the blackness. And it comes right out of Canada.

Congratulations Dr. McDonald. We are all proud.

(Tune-in to Quirks & Quarks this weekend to hear our interview with Canada's newest Nobel Laureate).