He rides his bicycle to work to study the theories behind some of humanity's more advanced science. Dr Robert Thompson is the affable American who may be one of few who can explain the theory behind invisibility and cloaking devices. He is also an outspoken advocate of cycleways in Dunedin. He spent some time trying to explain all that to David Loughrey.
It could have been the early exposure to the surface of Mars.
Perhaps it was a head-on crash he had with a car in Arizona while cycling.
Maybe it's the deformities the theory of general relativity predicts black holes cause in the space-time continuum.
It is more likely all those influences, both prosaic and cosmic, have shaped University of Otago research fellow Dr Robert Thompson.
Dr Thompson's life features two notable streams of activity that attract the interest of the passer-by.
From his shared office space in the Science 3 block at the University of Otago, under the watchful, knowing eyes of Albert Einstein, he studies the theories behind cloaking devices and invisibility.
And when he's not doing that, he's doing good - good, of course, if you are the sort that thinks cycleways are the way of the future - as the spokesman of cycle lobby group Spokes.
Dr Thompson also breaks from the stereotypical scientist of the imagination, who we all know creates Frankenstein-style monsters in secret labs or are thin, nerdy types designing ray guns.
Instead, our man displays an easy abundance of ruddy good health and physical fitness that shines through in an affable nature.
If not the quiet American, he is definitely the affable American.
His work is of the sort that people, when they hear of it, say: ''Really? That's interesting.''
And it is.
The postdoctoral fellow in the department of mathematics and statistics was born in Ypsilanti, Michigan, in 1975.
He entered that province of the space-time continuum because his father was doing master's degrees in naval architecture and nuclear engineering as part of his work for the Coast Guard, which in the US is a part of the armed forces.
''We moved around quite a bit,'' Dr Thompson says.
After just a few months in Ypsilanti, the family moved to Washington DC, then to New Orleans, then to Alaska, then back to Washington DC.
But that peripatetic existence - and a regular removal from the latest state he called home - was not enough to faze Dr Thompson.
There is no suppressed pain on offer for those looking for cracks.
''It's probably not for everyone, but I thought it was quite good,'' he says.
''I got to see a lot of different things. It was always sort of an adventure for me.''
That was helped by having three sisters in his family of six.
And it led him to places that would help shape his life.
''I'd always been interested in space, and physics, and that sort of thing,'' he says.
''I'd wanted to be - well, of course when you're a kid, every kid wants to be - an astronaut.''
It was in the small New Orleans city of Slidell, which features the Michoud Assembly Facility, which makes space shuttle external fuel tanks, and a Nasa computer centre, that interest was developed.
''Across the street from us there was an engineer associated with Nasa.
''I remember very clearly one time he invited me in and showed me this big picture of the surface of Mars that had been taken by one of the Viking landers. That, for me, was a defining moment.
''You see this ... wow; that's the surface of another planet.
''It was quite a big thing for me.''
A degree in astronomy, though, did not keep his attention, so his focus changed to theoretical physics.
Fast forward through university in Arizona and Virginia Tech, a post-graduation two-year hitch-hike-around-the-world trip that started in New Zealand (after he saved money working in an Alaskan fish factory), a PhD in general relativity and quantum field theory in the vicinity of black holes, a university posting in Lisbon, Portugal, to a move to his job at Otago in 2009.
Then there was a $345,000 Marsden Fast Start grant in 2012 to look at the mathematics underpinning transformation optics, which is making invisibility a reality.
There is one issue here - while cloaking devices are at the very apex of cool things, the explanation of the theories does glaze the eyes of even the moderately intelligent.
Here's the general idea, though: in 2006, a team at North Carolina's Duke University built the world's first cloaking device.
Dr Thompson's job is to work on the mathematical framework that ''puts this cloaking stuff on a firmer theoretical footing''.
''The way it works is a bit like a lens, but instead of focusing or de-focusing, you want something that will take light and divert it around a region as if nothing was there.
''You're not going to find anything in nature that does this, so you have to build something.''
Scientists built ''meta-materials with circuits printed on'', with each circuit mimicking the response to passing electromagnetic waves.
''You can create an artificial material that gives control over the way light responds, and design something that not just reflects light but brings it back around''.
But while cloaking was ''cool'', the technology developed was more likely to be used for devices that use electro-magnetic waves.
''Given the ubiquity of antennas in modern society - your smartphone, your Wi-Fi, everything - one of the major applications for this kind of stuff is going to be in antenna design.
''But antenna design is maybe a little bit more boring than cloaking.''
Cloaking and antennas, however, were ''what the engineers do''.
''I'm much more interested in the basic science of the propagation of light through stuff.''
Dr Thompson says the mathematics is very close to that in black holes and general relativity.
''It's all based on the same kind of stuff.
''Basically, it's a way of mathematically describing these meta-materials in a way that is consistent with the theories as we understand them, in terms of the theories of electrodynamics and gravity.
''In the way, all these modern theories are expressed - can we include a mathematical description of these meta-materials as well?''Dr Thompson says his work is - mostly - enjoyable.
''When things come together, and the mathematical calculations are working, then it's quite motivating, because you think you're on the path to discovering something new that no-one else has discovered before.''
And while there is an aspect of ''basic scientific curiosity'' to his work, it will help the applications of the science in future to ''build better things''.
Then there's cycling.
Dr Thompson is spokesman for Dunedin volunteer cycling advocacy group Spokes, which is keen to promote separated cycleways.
''I started riding a bike as a child of 3 or 4 years old - I guess the difference is I never stopped,'' he says.
While training for the University of Arizona cycling team, he was out in the desert, riding back into town, when a car turned in front of him, ''I went into the windshield, up over the top of the car, off the back.
''They scraped me up off the pavement and took me to the hospital in an ambulance.
''I was pretty beat up.''
The importance of cycleways became apparent on a trip to Copenhagen, in Denmark.
''Man, that was just an eye-opener. Suddenly you could just ride around and you didn't have to worry about anything.''
That led to a sudden realisation ''it doesn't have to be the way that it is''.
Dr Thompson got involved with Spokes in 2010, and says of opposition to the idea: ''It requires an adjustment to your way of thinking.
''They're popping up all over the world, in the United States, even Texas, and have taken off in the last five to 10 years.
''It's nothing new, and they are working; reducing accidents and increasing numbers riding bikes.''
