With new scientific discoveries announced on a daily basis, it is tempting to envision an age when the annals of science have nothing new to teach us.

But did you know that 96 per cent of the universe remains a complete mystery to mankind and that even the remaining four per cent contains huge gaps in our knowledge?

Nobel Prize-winning physicist William Phillips has dedicated his career to filling in some of those gaps, with his work on laser cooling – zapping atoms with light to slow and, therefore, cool them down – leading to the much-improved atomic clocks that make the global positioning system as accurate as it is.

“The whole idea sounds crazy because, usually, when you shine light on something it turns hot,” Prof. Phillips admits, a few hours after landing in Malta for a brief three-day visit on the invitation of André Xuereb, visiting researcher at Queen’s University, Belfast, with the support of the US Embassy.

Starting in the late 1970s, physicists realised that the thought might not be as crazy as it sounds.

By the following decade, scientists, such as Prof. Phillips and Steven Chu (the current US Secretary of Energy), were working at the idea round the clock.

They discovered that by shining lasers tuned to a colour frequency fractionally lower than an atom’s preferred one, they could slow atoms down dramatically and, therefore, cool them.

“Cool” does not quite convey just how cold such atoms get.

“Room temperature is about 300C above absolute zero. And laser cooling has brought atoms down to just under one billionth of a degree above that.”

At this point, Prof. Phillips launches into a 45-minute explanation of atomic properties, Heisenberg’s uncertainty principle, theoretical limits to temperature and the properties of light.

All throughout, Prof. Phillips’s infectious enthusiasm shines through, with explanations almost as energetic as the atoms he has spent his life slowing down.

Winning 1997’s Nobel Physics Prize “hit me like a bolt out of the blue,” he says. Prof. Phillips shared the prize with his colleagues Prof. Chu and Claude Cohen-Tannoudji for their work on laser cooling.

He chuckles. “My life changed in ways I could barely imagine.

“And it gave me the opportunity to meet people who are actually famous.”

It also meant many more people were suddenly eager to meet him, Prof. Phillips concedes.

“Lectures and speaking engagements take up much of my time these days, so I spend less time in the lab actually doing the physics,” he says.

“But the great thing is that I have this team of young physicists who are so energetic and creative, coming up with things I would never have dreamt about.”

He traces a line of Nobel Physics Prizes related to his 1997 win, from the 2001 award for work on the Bose-Einstein condensate (where a cluster of boson atoms is cooled to so close to absolute zero that individual atoms become indistinguishable from the whole) to the 2005 prize for optical frequency standards – “a new way of doing clocks using optical frequencies on laser-cooled clocks”, he explains.

Things came full circle with this year’s Nobel Physics Prize going to David Wineland for his experiments on laser-cooled ions.

“David was the guy who got me into laser cooling in the first place. He was doing it before anyone else! So it’s great to see his work rewarded.”

Prof. Phillips’s Nobel Prize also catapulted him to the attention of the Vatican’s scientific community, which subsequently made him a member of the Pontifical Academy of Sciences.

One gets the sense he is slightly uneasy being asked about the juxtaposition of his scientific mind and religious faith. Are the two at odds?

“Some people want to put religious faith and science at odds but I don’t see any reason why.” He pauses before quoting Pope Leo XIII: “Truth cannot contradict truth.”

Polarised, absolutist perspectives on either side concern him.

“You have people rejecting science because they believe it contradicts their religious faith.

“We can’t afford that in our technological era.

“At the same time, if scientists think people of faith are superstitious simpletons, then they are rejecting a huge percentage of the population.”

But it is his science, rather than personal faith, that Prof. Phillips is known for. He has left an indelible imprint on atomic clocks, GPS and quantum physics... and there might be more to come.

“If it weren’t for quantum mechanics in 1925, you couldn’t have a cell phone. Nobody was thinking about cell phones back then. The scientific discovery came first and the application came later. And that’s the way it always works.”

Having just turned 64, Prof. Williams would be forgiven for hanging up his lab coat. But his enthralling explanations of atomic properties are evidence – if any were needed – that his passion for science has not waned over time.

“I love explaining science and helping people, especially children, get excited about it.

“There’s so much of the world that’s yet to be discovered. What could be better than that?”