Question: What are the discoveries that have lead up to your current work?

David Ho answered on 9 Nov 2018: last edited 9 Nov 2018 7:07 pm

I study a type of particle called a “magnetic monopole”. All the magnets we’ve ever found in nature have a North and a South pole, and you can’t split the two — if you cut a magnet in half you get two more magnets, each with North and South poles. As you can probably tell from the word, a magnetic monopole would just be a North or a South pole on its own…we’ve never seen one of these.

Not very long after people discovered the electron, which is a particle that feels the electric force, a man named Paul Dirac in the 1930s found out that the same equations that describe the electron could also describe a magnetic monopole. This was nice to know, but nobody really thought of it too much because we’d never seen one.

The next big discovery came in 1974, by two scientists named Gerard ‘t Hooft and Dmitri Polyakov. They were studying theories that people were trying to use to describe three of the forces (electromagnetism, the strong nuclear force and the weak nuclear force) at the same time. They found that these theories showed that magnetic monopoles should have been produced shortly after the Big Bang, so if these theories are true then the particles must exist! That set off a lot of people looking for them, but in those 30+ years we still haven’t found one.

I’m working to try and predict how we might be able to produce these sneaky particles. We think our best chance is at the Large Hadron Collider, the world’s biggest particle collider experiment. If we take lead atoms and fire them at each other at incredible speeds, there’s a possibility we might make monopoles. In fact that’s what’s happening right now as we speak, the first collisions of the current experiment started yesterday! So the next major discovery might be announced pretty soon…