Mathematician Marcus du Sautoy considers how many of the problems being addressed by academics are no longer amenable to a single subject focus.

A few months after I took up my chair as the Simonyi Professor for the Public Understanding of Science I got a phone call from a journalist. “The Nobel Prize for Medicine was announced this morning for the discovery of telomeres. I wonder if you could explain what a telomere is?”

I am a mathematician. Sequences of nucleotides at the ends of chromosomes are not my usual poison. Of course the title of my Chair does give journalists the impression that I might be able to explain the whole of science. I guess the last person who was able to do that was probably living in the nineteenth century.

Shortly after that phone call, the BBC asked me to make a programme about consciousness for them. Again my first reaction was: “But I’m a mathematician.” Yet when I began to think about the subject matter, I realised that it’s far from clear in whose domain a subject like consciousness lies. Philosophy, neuroscience, psychology, physics, biology, chemistry – even maths. The conclusion I came to at the end of making the programme was that it lies in all of them. Rather like the brain which shows extraordinary integration to create that sense of one identity out of many millions of neurons, the way to crack the big problems is not to use ideas from a single discipline, but to integrate modes of thinking from across disciplines.

One of the joys of my job as Professor for the Public Understanding of Science has been the chance to stick my head out of the world of mathematics and find out what is going on in the other subjects that surround me in the University Science Area. It’s an increasing revelation across the academic world that many of the problems we are trying to crack are not amenable any more to a single subject focus. Traditionally the picture of a university looked like a collection of isolated silos: the chemistry department here, the maths department over there. The truth is that increasingly the picture of the research being done looks more like some intricate Venn diagram of intersecting disciplines. Mathematical biology. Computational chemistry. The physics of finance. This interplay between subjects is absolutely necessary if we are going to tackle such complex problems as climate change, virus spread, economic stability and population growth. This is the motivation for the creation of bodies like the Santa Fe Institute or the Oxford Martin School that have championed this multi-disciplinary approach to the problems of the twenty-first century.

Even questions that don’t at first sight have an obvious multi-disciplinary nature could equally benefit from discussions with those in the department across the street. The low-lying fruit probably exists in learning the language spoken by another department and applying it to the problems in your own field. I have seen how an economist who learnt gauge theory from a physicist, a mathematical language to describe the dynamics of elementary particles, was able to apply this new language to model the rate of change of inflation, a notoriously difficult problem given that the basket of goods you’re trying to track changes with time as do the prices of the goods. But the breakthrough came only as a result of two previously alien cultures finding a common language of discourse.

In my own area of research, number theory, the most exciting progress on the Riemann Hypothesis, the great unsolved problem of mathematics, came from a chance meeting of a mathematician and a physicist over tea. That conversation led to the discovery that energy levels in large atoms like uranium have very similar patterns to certain ways of looking at prime numbers. That in turn has provided our best clue yet that it is the mathematics that underpins quantum physics which might be the right tool to tackle the Riemann Hypothesis.

Despite the exciting new bridges being built, we still have a long way to go in breaking down the silo mentality traditionally found in universities. When I started as the Professor for the Public Understanding of Science, one of the missions I set myself was to get people from different scientific disciplines in the university talking to each other, finding out each other’s research problems, and seeing if they might be sitting on tools in their own disciplines that might help others. I was amazed, talking to scientists, at how many had never set foot in each other’s buildings. An astronomer who visited me declared, “This is the first time I’ve been in the Mathematical Institute.” We’re physically so close that I can see his office from my office window. Yet academically, it seems like we were on opposite sides of the universe.

To try to counter this, I piloted a series of podcasts that successfully brought experts together to share their stories in a Radio 4, Start the Week-type package. It is a project that I believe has the potential to provide a powerful vehicle for facilitating inter-disciplinary dialogue.

Of course this compartmentalisation of subjects has its origins in the traditional model of education in schools. Pupils go from a history lesson to a maths lesson to a music lesson to a physics lesson and are barely aware that the subjects they have just been studying have any connection with each other. One of the reasons I made the BBC documentary The Story of Maths was to make the important connection between mathematics and history. Most people’s impression of mathematics is that it is a subject that was handed down in some great text book from the sky, that it’s always existed and is a finished subject. I think Fermat’s Last Theorem, for most, was exactly that – the last theorem. Maths has now been finished.

Profitable connections needn’t just be between traditional academic subjects. Complicite’s award-winning play A Disappearing Number brought the worlds of theatre and mathematics together in a piece that surprised many who came to see it. I spent many sessions with the company exploring the mathematics at the heart of the play, the mathematics that grew out of the relationship between English mathematician GH Hardy and Indian mathematician Srinivasa Ramanujan. The surprise for me was that it wasn’t just my mathematics that was stretching the actors creatively; the questions posed by the actors in turn pushed me mathematically, making me see my own subject in a new light.

As part of the project we developed a series of workshops for teachers to explore the ideas at the heart of the play. The drama teachers are all big fans of Complicite, internationally recognised as one of the greatest theatre companies in the world. So when we advertised the workshops they all ran to sign up immediately. But we made it a condition of the workshop that each drama teacher had to come with a maths teacher. For many the common-room conversation about the workshop was the first time the drama teacher had ever talked to the maths teacher. The workshops had the effect of creating a new bond between two departments in school that had previously not seen any link.

It is one of many stories that have contributed to my belief that the best education would be one where we tore down the walls between classrooms and taught education in a more holistic way. Of course in some ways that is what Oxford has been doing for centuries. The college system has always been about cross-subject dialogue. As an undergraduate at Wadham, I sat with my fellow students talking about Derrida and deconstructionism, the poetry of Omar Khayyam, the philosophical ideas of Karl Popper, and into this mix it was my place to explain mathematics’ important place in this intellectual melting pot. Part of the reason I was drawn to the Professorship for the Public Understanding of Science is that I’ve been practising it ever since I came up to Oxford as an undergraduate.

One of the many joys of being a professor in New College is the continuation of those inter-disciplinary discussions, finding myself sitting next to fellows from such different disciplines and sharing ideas, stories, problems. This summer the mathematics department moves into its beautiful new building on the Radcliffe Infirmary site. The building aims to create not just a place to facilitate conversations between mathematicians, but to invite dialogue with the many people we hope will pass through its doors from beyond the world of mathematics.

The building is part of a larger project in the University – not only to facilitate the chance cup of tea between researchers within the University in seemingly unrelated fields, but to create bridges between the laboratory and the art gallery, the lecture theatre and the factory, the university library and the corridors of Westminster. The more we learn to speak each other’s languages, ask each other new questions, the more hope there is of finding the answers to the problems that have stubbornly eluded previous generations.

Marcus du Sautoy OBE (Wadham, 1983) has been the Simonyi Professor for the Public Understanding of Science since 2008. A fellow of New College, and winner of the 2001 Berwick Prize of the London Mathematical Society, he regularly writes for The Times, The Guardian and The Daily Telegraph. He is a member of the University’s Mathematical Institute and is a Senior Media Fellow of the EPSRC.