In 2004, the Italian theoretical cosmologist Valeria Pettorino wrote her doctoral thesis on “dark energy in generalized theories of gravity.” As a side project, she translated the opening lines of Dante’s Divine Comedy into a geometry problem.

“I felt there was mathematics already within Dante’s writing,” Pettorino said recently.

Dante’s epic poem, in Mark Musa’s translation, begins:

Midway along the journey of our life

I woke to find myself in a dark wood,

for I had wandered off from the straight path.

Pettorino’s translation reads:

Given a line segment AB of size equal to our life path, consider its midpoint M. If D is a man called Dante, D shall be coincident with M.

The segment AB shall be contained in a dark field DF.

Assuming that a circumference C exists, circumscribed to the dark field DF, verify that the straight line r is external to such circumference.

This reimagining, part of a creative writing group project, was published in a collection titled Faximile — an homage to admired authors and texts, in which the Pythagorean theorem became a story, The Iliad became a football match, and the Italian constitution was rendered in hendecasyllabic verse. “We liked the originals, and we wanted to play with them and understand them better,” Pettorino said.

She has approached cosmology in the same spirit, using storytelling from multiple angles as a guiding principle. After earning her Ph.D. in 2005, she traveled the world, hopping between institutions in Heidelberg, New York, Geneva and Valencia, as well as Naples, Turin and Trieste in her native Italy, alternating between observational, theoretical, methodological and statistical points of view in her study of the cosmos — a dark wood, rather like Dante’s. She considers all of these approaches necessary for unraveling the nature of dark matter and dark energy, little-understood substances that together comprise 95 percent of the universe.

It is perhaps not surprising that in 2016 Pettorino landed at the CosmoStat laboratory at CEA Saclay, a research institute 15 miles south of Paris. At CosmoStat, cosmologists and computer scientists collaborate to develop new statistical and signal-processing methods for interpreting the vast volumes of data acquired by modern telescopes. This summer, Pettorino helped complete the final analysis of data from the European Space Agency’s Planck space telescope, which mapped the early universe with unprecedented precision. Her main focus now is Euclid, the agency’s next major space telescope, set to launch in 2022. Euclid will gather 170 million gigabytes of data about billions of galaxies, slicing the universe at different epochs and tracking its evolution under dark influences.

Quanta Magazine spoke with Pettorino over Skype this summer as she helped organize the annual EuroPython conference for users of the Python programming language, among other extracurricular commitments. The interview has been condensed and edited for clarity.

You have many interests. Tell me how you became a cosmologist.

I hadn’t thought about cosmology at all when I started physics, and even then I wasn’t very convinced about physics in itself. But physics offered me a good opportunity to combine several different interests. At the time, I was living in Naples, my city. I really wanted to follow a path that would allow me to get to know people, live in different places, and learn languages. I certainly liked logic and mathematics. And I heard about physics from my uncle, Roberto Pettorino, who was a string theorist; he told me about strings, multiple dimensions, time travel. And I loved science fiction. The authors I read most were Philip José Farmer and Jack Vance — the stories had adventure, and different technologies, and they were very realistic, creating new worlds in great detail with things that don’t exist but could very easily have existed. I liked challenges. At that time, I was taking acting classes and creative writing classes. And then I just said, “Let’s do physics!” I was curious about the whole picture, and physics looked to me like a good combination of logic, of communication, of imagination. My main goal was to learn, to increase my knowledge, to satisfy my curiosity.

How did you eventually find cosmology?

I started physics as an undergraduate at the end of 1997, and then in 1998 there was the cosmic acceleration discovery, revealing that a lot of the universe was completely unknown, and this immediately attracted my curiosity. What happened was that independent observations by two different supernova research teams showed very surprising results: Cosmologists were expecting the universe to be expanding after the Big Bang, and since gravity attracts things toward each other, the expectation was that the universe’s expansion was decelerating. Evidence from supernova explosions showed that the expansion is, instead, accelerating — as if there is some extra form of energy that counteracts gravity and increases the velocity of the expansion. This is generically named “dark energy.”

Since 1998, many other experiments have confirmed the same picture: Normal atoms only account for about 5 percent of the total energy budget in the universe. There is an extra 25 percent that is in the form of “dark matter.” Dark matter still feels gravity, but we don’t observe it directly; it acts as a glue that allows structures, like galaxies and clusters of galaxies, to form. And then there is the rest — 70 percent — which is dark energy, and which should be responsible for cosmic acceleration.