The Faculty Member: Peter Onyisi

Credit: Jeff Wilson

Physicist and Assistant Professor in the College of Natural Sciences. Interviewed by Marc Airhart.

You were part of the team at CERN working with the Large Hadron Collider (LHC) that confirmed the existence of the Higgs boson particle. What questions did that discovery open up?

The mass of the Higgs boson turns out to be very strange, neither too light nor too heavy to lend itself to easy explanations. That raises the possibility that our universe is inherently unstable. If that’s true, the universe might eventually destroy itself, assuming we don’t find any new physics to repair the problem. It’s actually easy to fix if you add more particles to the theory.

So it’s possible there are more particles waiting to be discovered?

According to Supersymmetry, a theoretical framework that suggests every particle has a partner with similar but not quite the same properties, there should actually be five particles in the Higgs boson sector, not one. If these other particles exist, they would be totally different from the one we’ve found, but they would also be Higgs bosons. So we’ll start up the machine again and in 2016 you might hear, “The LHC discovers second Higgs boson.” 

Credit: ATLAS image provided by CERN

Supersymmetry is appealing because it solves a lot of problems in physics, including dark matter. It’s the kitchen sink of solving theoretical problems. The downside is that no one has seen evidence of it yet, though lots of people are looking, of course.

You had only been involved with the Higgs search for about a year and a half when the discovery was announced. But there were people who had spent decades working on it. How did it feel to be the new person?

For me, I happened to be in a good place at a good time. I wanted to be at the LHC, so it wasn’t that accidental. If I had been a postdoc five years earlier, I would not have had the opportunity. In the long-term scheme of things, I was fairly lucky.

“In 2016 you might hear, ’The LHC discovers second Higgs boson.’”

What do you enjoy about teaching?

It’s like being a tour guide. You get to show people the wonders of physics, and sometimes they really enjoy it. You might say, “Look at this fantastic result or experiment.” When a student gets it or says, “Oh, wow, this is really neat,” then that makes my day.

Peter with postdoc Yuriy Ilchenko and (former) undergraduate Victor Rodriguez in Geneva.