F. Duncan M. Haldane, the Eugene Higgins Professor of Physics at Princeton University, was awarded the 2016 Nobel Prize in Physics on October 4.

Haldane has taught at Princeton since 1991 and studies the field of condensed matter physics. He shares the prize with his two colleagues, David J. Thouless and J. Michael Kosterlitz. The three British-born physicists have been studying quantum mechanics for decades—using topology, a branch of mathematics that describes properties that only change step-wise, to challenge established theories.

In an interview with the Chief Scientific Officer of Nobel Media, Haldane spoke about receiving the news at 4:30 am. When asked what he did after being told he had won, he responded, “Had a cup of coffee.”

The team was honored this week for their topological research. They “used advanced mathematical methods to study unusual phases, or states, of matter, such as superconductors, superfluids or thin magnetic films.” Now, thanks to their work, scientists can search for new phases of matter.

“We didn’t discover [the things quantum mechanics can do] earlier because it was just difficult to actually even imagine that quantum mechanics might do these kinds of things,” Haldane said. “It’s very difficult to know whether something is useful or not, but one can know that it’s exciting.”

A press conference was held on Tuesday at Princeton University. Watch the video below for an address from the University’s president, thoughts from Haldane himself and a Q&A with attendees.