TO celebrate the Year of Young People, every week in 2018 The National is giving a platform to a young person. This week, 25-year-old cosmologist Benjamin Giblin

IN the shadow of Arthur’s Seat, atop an ancient hill of dormant volcanic rock, is Edinburgh’s Royal Observatory. The old-timey title, 19th-century brickwork and leafy location create what seems an unlikely setting for cutting-edge research into the nature of the universe. Nevertheless, the observatory boasts more than its fair share of the foremost, field-defining, world-leading cosmologists and astrophysicists. Oh, and yours truly, a PhD student lucky enough to spend his nine-to-fives in their company.

I have called Edinburgh “home” for just over three of my 25 times around the Sun. When I am not recovering my breath from the daily cycle up to the observatory (or frequenting the city’s open-mic nights with folk-rock outfit The Darjeeling Feeling) I am thinking deeply about the cosmos. More specifically, I spend my time examining images captured with a state-of-the-art telescope atop a mountain in Chile.

In these images, I search for some sign of a mysterious substance called “dark matter”, which constitutes roughly 80% of all of the mass in the universe. On the face of it, this seems an impossible task, for dark matter neither absorbs nor emits light whatsoever. It is completely invisible.

Thus, how can we possibly detect this elusive material? Is my PhD doomed to fail? Fortunately, nature has thrown the poor students of the universe a bone. Anything with mass, including dark matter, distorts the fabric of reality (picture a heavy bowling ball distorting the fabric of a mattress). This phenomenon is what the cosmologist would call “spacetime curvature” and what the layperson would call “gravity”. The gravity of dark matter distributed throughout space, bends the light from distant galaxies as it travels towards us. This effect, termed “gravitational lensing”, causes the observed images of said galaxies to become stretched and distorted (imagine viewing a candle through a whisky glass). These lensing effects are detectable and are just one of several ways in which scientists can tell dark matter is out there. (Although it is not just out there … billions of dark matter particles are passing through these words as you read them off the paper!) Therefore, like a thief leaving fingerprints at the crime scene, dark matter’s gravitational calling card betrays this slippery customer. The game is afoot and there is hope for my PhD after all! However, dark matter is but one small piece of the puzzle. Our observations also point to an even more nefarious character, by the name of “dark energy”, whose offences include accelerating the expansion of the universe.

There is clearly a great deal more detective-work required to crack this case. Though you won’t find me complaining; Scotland’s breath-taking Highlands, ancient capital and warming national drink provide the perfect recourse for pondering the secrets of the cosmos.

Is there a more thrilling discussion of the wonders of space, than that which is had over a few wee drams?